Method and apparatus for mitral valve chord repair

Abstract

To provide a method and apparatus for mitral valve chord repair.SOLUTION: Methods and devices for transvascular prosthetic chordae tendineae implantation are disclosed. A catheter is advanced toward the left atrium. From an atrium side, the catheter can be anchored to a superior surface of a mitral valve leaflet, and a leaflet anchor can be advanced into the mitral valve leaflet to secure the mitral valve leaflet to a leaflet suture. A ventricular anchor is anchored to the wall of the ventricle to secure the ventricular wall to a ventricle suture. The leaflet suture and the ventricle suture are tensioned and connected by a suture lock to form prosthetic chordae tendineae.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 040389, filed June 17, 2020, the entire contents of which are incorporated herein by reference.

[0002] All applications identified in the PCT request as having foreign or domestic priority claims filed with this application are incorporated by reference. [Background technology]

[0003] The present disclosure relates to mitral valve repair or replacement, and more particularly to methods and devices for mitral valve reshaping, repair and / or mitral valve chordae replacement to adequately restore mitral valve function from mitral regurgitation.

[0004] The heart has four heart valves that allow blood to pass in one direction through the four ventricles of the heart: the tricuspid, mitral, pulmonary, and aortic valves. The four chambers are the left and right atria (upper chambers) and the right and left ventricles (lower chambers).

[0005] The mitral valve is made up of two leaflets, called the anterior and posterior leaflets. These leaflets open and close in response to pressure exerted on them by the heart's contractions. Several problems can arise with the mitral valve. One such problem is mitral regurgitation (MR). Mitral regurgitation is a condition in which the mitral valve leaflets do not close properly, which can result in leakage from the mitral valve. Severe mitral regurgitation can adversely affect cardiac function and potentially reduce a patient's quality of life and lifespan.

[0006] Techniques have been developed to treat mitral regurgitation. These techniques include heart transplantation, valve replacement or repair, chordae shortening or replacement, and mitral annulus repair, also known as valvuloplasty. The choice of technique depends on the stage and etiology of the disease. Summary of the Invention [Problem to be solved by the invention]

[0007] Certain surgical and transapical approaches have been proposed for chordae replacement or repair, but despite these proposals, there remains a need for transvascular approaches to chordae replacement or repair, particularly but not limited to, to reduce or eliminate MR. [Means for solving the problem]

[0008] A method and device for transvascular artificial aponeurosis implantation is disclosed. A catheter is advanced toward the left atrium. From the atrial side, the catheter is anchored to the superior surface of the mitral valve, and a mitral valve anchor can be advanced into the mitral valve and secure the mitral valve to the leaflet sutures. A ventricular anchor is anchored to the ventricular wall, securing the ventricular wall to the ventricular sutures. The leaflet sutures and ventricular sutures may be tensioned and connected by a suture lock to form an artificial spine.

[0009] According to one embodiment (Example 1) of the present disclosure, a tissue anchor includes a hub, a suture portion extending proximally from the hub, a helical anchor extending distally from the hub, and a second anchor axially movable distally from a first configuration to a deployed second configuration to engage tissue and prevent disengagement of the helical anchor.

[0010] According to another aspect of the present disclosure (Example 2) related to Example 1, the second anchor has prongs extending between a proximal end and a pointed distal end.

[0011] According to another embodiment (Example 3) of the present disclosure in accordance with Example 2, the branch portions are supported by supports.

[0012] According to another embodiment (Example 4) of the present disclosure in accordance with Example 3, the support has an annular structure.

[0013] According to another aspect of the present disclosure (Example 5) according to Examples 1 or 4, the support receives a tubular structure of a deployment system for distally advancing the support relative to the helical anchor.

[0014] According to another embodiment (Example 6) of the present disclosure in accordance with Example 2, the hub has axially movable prong guides that receive the prongs.

[0015] According to another aspect of the present disclosure (Example 7) related to Example 6, the branch guide has a deflection surface for deflecting the branches at a launch angle that is angled radially outward in the distal direction.

[0016] According to another embodiment (Example 8) of the present disclosure in accordance with Example 7, the launch angle is in the range of approximately 30° to 45°.

[0017] According to another embodiment (Example 9) of the present disclosure in accordance with Example 1, the hub has an axially movable opening that receives the second anchor.

[0018] According to another embodiment (Example 10) of the present disclosure in accordance with any one of Examples 1 to 9, the device further includes a core wire attached to the hub and extending concentrically through the helical anchor.

[0019] According to another embodiment (Example 11) of the present disclosure in accordance with any one of Examples 1 to 10, the device further includes a suture anchor guide extending proximally from the hub.

[0020] According to another aspect of the present disclosure (Example 12) in accordance with Example 11, in the deployed second configuration, the second anchor extends through the suture anchor guide.

[0021] According to another aspect of the present disclosure (Example 13) in accordance with Example 12, the second anchor extends through an opening in the suture anchor guide.

[0022] According to another aspect of the present disclosure (Example 14) in accordance with Example 13, when the second anchor is moved to the deployed second configuration, the second anchor is operable to penetrate the suture anchor guide.

[0023] According to another embodiment (Example 15) of the present disclosure in accordance with Example 1, the device further comprises a radiopaque marker supported by the second anchor.

[0024] According to another embodiment (Example 16) of the present disclosure in accordance with any of Examples 1 to 15, the device further comprises a core wire attached to the hub and extending concentrically through the helical anchor.

[0025] According to another embodiment (Example 17) of the present disclosure in accordance with Example 16, the catheter further comprises a radiopaque marker movably supported in the axial direction by the core wire.

[0026] According to another embodiment (Example 18) of the present disclosure in accordance with Example 16, the device further includes a spring supported on the core wire.

[0027] According to another embodiment of the present disclosure (Example 19) in accordance with Example 16, the core wire extends distally beyond the helical anchor.

[0028] According to another embodiment (Example 20) of the present disclosure in accordance with Example 16, the catheter further comprises a distal stopper provided on the core wire operable to limit distal movement of the radiopaque marker.

[0029] According to another aspect (Example 21) of the present disclosure related to Example 1, the helical anchor further includes a tissue penetration point at a distal end thereof, and a turn-up portion on the helical anchor located proximal to the point and configured to resist rotation of the helical anchor out of engagement with the tissue.

[0030] According to another aspect of the present disclosure (Example 22) according to any of Examples 1-21, the second anchor is operable to increase the anchor torque resistance of the tissue anchor by 2 to 5 times compared to the anchor torque resistance of the tissue without the second anchor.

[0031] According to another embodiment (Example 23) of the present disclosure in accordance with any of Examples 1 to 21, the anchor torque resistance of the helical anchor having the second anchor is 2 N / cm to 5 N / cm.

[0032] According to another aspect of the present disclosure (Example 24) according to any of Examples 1-21, the second anchor is operable to increase the anchor torque resistance of the tissue anchor by at least two times compared to the anchor torque resistance of the tissue anchor without the second anchor.

[0033] According to another embodiment (Example 25) of the present disclosure in accordance with any of Examples 1 to 21, the anchor torque resistance of the helical anchor is greater than 2 N / cm.

[0034] According to one aspect (Example 26) of the present disclosure, a method for implanting transvascular artificial chordae includes the steps of advancing a catheter into the left atrium and through the mitral valve into the left ventricle; deploying a ventricular anchor from the catheter to the wall of the left ventricle by rotating a spiral tissue anchor toward the wall of the left ventricle; deploying a second tissue anchor in the wall of the left ventricle to inhibit dislodgment of the spiral tissue anchor; maintaining ventricular sutures attached to the ventricular anchor and extending proximally through the catheter; securing a leaflet anchor catheter to the mitral valve leaflets from the atrial side; advancing leaflet anchors from the catheter through the mitral valve leaflets with the leaflet anchor catheter secured to the leaflets to secure the mitral valve leaflets to the leaflet sutures, the leaflet sutures extending proximally through the catheter; and securing the leaflet sutures to the ventricular sutures to limit movement of the leaflets toward the left atrium.

[0035] According to another aspect (Example 27) of the present disclosure related to Example 26, the step of deploying the second tissue anchor includes the step of axially advancing the second tissue anchor distally relative to the helical tissue anchor.

[0036] According to another aspect of the present disclosure (Example 28) related to Example 26, the step of deploying the second tissue anchor increases the anchor torque resistance of the ventricular anchor by 2 to 5 times compared to the anchor torque resistance of the ventricular anchor without the second anchor.

[0037] According to another embodiment (Example 29) of the present disclosure in accordance with Example 26, the anchor torque resistance of the tissue anchor and the second tissue anchor is between 2 N / cm and 5 N / cm.

[0038] According to another aspect of the present disclosure (Example 30) related to Example 26, the second tissue anchor increases the anchor torque resistance of the ventricular anchor by at least two times compared to the anchor torque resistance of the ventricular anchor without the second anchor.

[0039] According to another embodiment (Example 31) of the present disclosure in accordance with Example 26, the anchor torque resistance between the second tissue anchor and the ventricular anchor is at least greater than 2 N / cm.

[0040] According to one aspect (Example 32) of the present disclosure, an access system for directing a ventricular anchor sheath to a target site in the left ventricle includes: a delivery catheter having an elongated, flexible tubular body having a proximal end, a distal end, a central axis, and a steering zone near the distal end, the steering zone being actively deflectable to provide a delivery catheter curve that resides in a delivery catheter curve plane; and an anchor sheath axially advanceable through the delivery catheter, the anchor sheath having a proximal preset curve and a distal preset curve that reside in a proximal preset curve plane, the anchor sheath configured to rotate within the delivery catheter to bias the proximal preset curve plane into alignment with the delivery catheter curve plane in response to axial alignment of the proximal preset curve within the delivery catheter curve.

[0041] According to another aspect of the present disclosure (Example 33) in accordance with Example 32, the distal preset curve lies in a distal preset curve plane that is angled from the proximal preset curve plane.

[0042] According to another embodiment of the present disclosure (Example 34) according to Example 32 or 33, the delivery catheter curve is actively adjustable over a range of at least 10 to 150 degrees.

[0043] According to one aspect (Example 35) of the present disclosure, an access system for directing a ventricular anchor sheath to a target site in the left ventricle includes: a delivery catheter having an elongated, flexible tubular body having a proximal end, a distal end, and a steering zone near the distal end, the steering zone being actively deflectable to provide a delivery catheter curve that lies in a delivery catheter curve plane; and an anchor sheath axially advanceable through the delivery catheter, the anchor sheath having a proximal preset curve and a distal preset curve that lies in a proximal preset curve plane, the proximal preset curve and the delivery catheter curve being configured to cooperate to provide a tactile indication of rotational alignment of the anchor sheath within the delivery catheter.

[0044] According to one aspect (Example 36) of the present disclosure, a ventricular anchor delivery sheath comprises an elongate, flexible tubular body having a proximal end, a distal end, and a longitudinal axis, a proximal preset curve of the tubular body, and a distal preset curve of the tubular body.

[0045] According to another aspect of the present disclosure (Example 37) related to Example 36, the proximal preset curve lies in a first plane and the distal preset curve lies in a second plane, the second plane being rotationally angled from the first plane.

[0046] According to another embodiment (Example 38) of the present disclosure in accordance with Example 37, the second plane is rotationally angled from the first plane at an angle in the range of 40° to 75°.

[0047] According to another embodiment (Example 39) of the present disclosure according to Example 37 or 38, the distal preset curve has an angle in the first plane within the range of 5° to 60°.

[0048] According to another embodiment (Example 40) of the present disclosure in accordance with any of Examples 36-39, the length of the distal preset curve is 50% or less of the length of the proximal preset curve.

[0049] According to another embodiment (Example 41) of the present disclosure in accordance with Examples 36-39, the length of the distal preset curve is 20% or less of the length of the proximal preset curve.

[0050] According to another embodiment (Example 42) of the present disclosure in accordance with Examples 36-41, the distance between the longitudinal center of the proximal preset curve and the longitudinal center of the distal preset curve ranges between 45 and 85 millimeters.

[0051] According to another embodiment (Example 43) of the present disclosure in accordance with Examples 36-41, the longitudinal center of the distal preset curve is within a range of 50-70 millimeters from the distal end of the ventricular anchor delivery sheath.

[0052] According to another embodiment of the present disclosure (Example 44) in accordance with Examples 36-41, the longitudinal center of the proximal preset curve is within a range of 100-145 millimeters from the distal end of the ventricular anchor delivery sheath.

[0053] According to another embodiment (Example 45) of the present disclosure in accordance with Examples 36-44, the device further comprises a distal anchor section having a foldable sidewall.

[0054] According to one embodiment (Example 46) of the present disclosure, a ventricular anchor delivery sheath comprises an elongate, flexible tubular body having a proximal end, a distal end, and a longitudinal axis, and a distal preset curve of the tubular body.

[0055] According to another embodiment (Example 47) of the present disclosure in accordance with Example 46, the longitudinal center of the distal preset curve is within a range of 50 to 70 millimeters from the distal end of the ventricular anchor delivery sheath.

[0056] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings, which illustrate only some embodiments in accordance with the present disclosure and should not be considered limiting in scope. [Brief explanation of the drawings]

[0057] [Figure 1] FIG. 1 illustrates placement of a ventricular anchor via a transseptal approach to the mitral valve, according to an embodiment. [Figure 2A] FIG. 2A shows a ventricular anchor. [Figure 2B] FIG. 2B illustrates a ventricular anchor, according to an embodiment. [Figure 2C] FIG. 2C is a perspective view of a ventricular anchor at the distal end of a ventricular anchor deployment tool, according to an embodiment. [Figure 2D] FIG. 2D is a perspective view of the proximal end of a ventricular anchor deployment tool, according to an embodiment. [Figure 2E] FIG. 2E is a partially exploded perspective view of a ventricular anchor and the distal end of a ventricular anchor deployment tool, according to an embodiment. [Figure 2F] FIG. 2F illustrates a ventricular anchor including a second anchor in a first configuration, according to an embodiment. [Figure 2G] FIG. 2G illustrates the ventricular anchor shown in FIG. 2F including a second anchor in a deployed second configuration, according to an embodiment. [Figure 3] FIG. 3 illustrates the deployment end of a catheter positioned to engage the leaflets of a mitral valve, according to an embodiment. [Figure 4] FIG. 4 illustrates a valve leaflet captured by a helical leaflet anchor and a needle traversing the leaflet from the atrium to the ventricle, according to an embodiment. [Figure 5] FIG. 5 illustrates a pledget-type leaflet anchor being deployed from a needle into a ventricle, according to an embodiment. [Figure 6A] FIG. 6A illustrates proximal retraction of the leaflet sutures to fold the pledget against the ventricular side of the leaflet, according to an embodiment. [Figure 6B] FIG. 6B is a detailed view of a pledget-type leaflet anchor, according to an embodiment. [Figure 6C] FIG. 6C is a detailed view of a pledget-type leaflet anchor, according to an embodiment. [Figure 6D]FIG. 6D is a detailed view of a pledget-type leaflet anchor, according to an embodiment. [Figure 7] FIG. 7 illustrates a deployed ventricular anchor and sutures and deployed leaflet anchors and sutures ready for tensioning and attaching the suture lock, according to an embodiment. [Figure 8] FIG. 8 is a perspective view of a distal end of a leaflet anchor delivery subsystem, according to an embodiment. [Figure 9] FIG. 9 is a perspective view of the proximal end of a leaflet anchor delivery subsystem, according to an embodiment. [Figure 10] FIG. 10 is a perspective view of a distal end of a leaflet anchor delivery subsystem, according to an embodiment. [Figure 11] FIG. 11 illustrates the advancement of a suture lock through the suture lock delivery subsystem over the leaflet anchor sutures and the ventricular anchor sutures to connect the leaflet anchor to the ventricular anchor, according to an embodiment. [Figure 12] FIG. 12 illustrates a suture lock in a locked position after tension has been adjusted and the suture tails have been cut, according to an embodiment. [Figure 13] FIG. 13 is a perspective view of the distal end of a suture locking delivery subsystem, according to an embodiment. [Figure 14] FIG. 14 is a perspective view of the proximal end of a suture locking delivery subsystem, according to an embodiment. [Figure 15] FIG. 15 is a partial exploded view of the distal end of a suture locking delivery subsystem, according to an embodiment. [Figure 16] FIG. 16 is a perspective view of the distal end of a suture cutting assembly, according to an embodiment. [Figure 17] FIG. 17 is a side view of a cutting assembly of a suture locking delivery subsystem with the cutting head not advanced to hold the suture prior to delivery, according to an embodiment. [Figure 18]FIG. 18 is a side view of a cutting assembly of a suture lock delivery subsystem with the cutting head advanced to deliver a suture, according to an embodiment. [Figure 19] FIG. 19 is a side view of a distal end of a torque driver configured to engage a suture lock and the suture lock, according to an embodiment. [Figure 20] FIG. 20 shows the proximal end of a suture lock, according to an embodiment. [Figure 21] FIG. 21 shows the distal end of a suture lock, according to an embodiment. [Figure 22A] FIG. 22A is a side view of a ventricular anchor delivery subsystem according to one aspect of the present application, according to an embodiment. [Figure 22B] FIG. 22B is a side view of the proximal portion of the ventricular anchor delivery subsystem shown in FIG. 22A, according to an embodiment. [Figure 22C] FIG. 22C is a side view of the intermediate portion of the ventricular anchor delivery subsystem shown in FIG. 22A, according to an embodiment. [Figure 22D] FIG. 22D is a side view of the distal portion of the ventricular anchor delivery subsystem shown in FIG. 22A, according to an embodiment. [Figure 22E] FIG. 22E is a longitudinal cross-sectional view taken along the portion shown in FIG. 22D, according to an embodiment. [Figure 22F] FIG. 22F is a longitudinal cross-sectional view along a mandrel that may be used to form the distal portion of the ventricular anchor delivery subsystem shown in FIG. 22A, according to an embodiment. [Figure 22G] FIG. 22G is a side view of an example of a distal end of a delivery catheter articulated into a first curve, according to an example embodiment. [Figure 22H] FIG. 22H is a perspective view of an example of a ventricular anchor sheath preset having a first curve and a second curve, according to an example embodiment. [Figure 22I] FIG. 22I is a top view of the ventricular ancas sheath of FIG. 22H, according to an embodiment. [Figure 22J]FIG. 22J is a side view of the ventricular ancas sheath of FIGS. 22H-I, according to an embodiment. [Figure 22K] FIG. 22K is a side view of the ventricular ancas sheath of FIGS. 22H-J, according to an embodiment. [Figure 22L] FIG. 22L illustrates placement of a ventricular anchor with the ventricular anchor sheath of FIGS. 22H-K and the delivery catheter of FIG. 22G, according to an embodiment. [Figure 23A] FIG. 23A is a top view of a cutter catheter in accordance with one embodiment of the present application, in accordance with an embodiment. [Figure 23B] FIG. 23B is a partial side cross-sectional view of the cutter catheter shown in FIG. 23A, according to an embodiment. [Figure 23C] FIG. 23C is a cross-sectional view taken along line 23C-23C of FIG. 23A, according to an embodiment. [Figure 24A] FIG. 24A is a front view of a cutter housing of the cutter catheter shown in FIG. 23A according to one embodiment of the present application, according to an embodiment. [Figure 24B] FIG. 24B is a side view of the cutter housing of FIG. 23A, according to an embodiment. [Figure 24C] FIG. 24C is a side cross-sectional view of the cutter housing of FIG. 23B, according to an embodiment. [Figure 24D] FIG. 24D is a view taken along line 24D-24D of FIG. 24C, according to an embodiment. [Figure 25A] FIG. 25A is a front view of an embodiment of a cutterhead, according to an embodiment. [Figure 25B] FIG. 25B is a side view of the cutterhead shown in FIG. 25A, according to an embodiment. [Figure 26] FIG. 26 is a side perspective view of a cutter head disposed in a cutter housing shown in phantom, according to an embodiment. [Figure 27] FIG. 27 is a side cross-sectional view of a handle of a cutter catheter according to one embodiment, in accordance with an embodiment. [Figure 28]FIG. 28 is a top view of an embodiment of sutures and pledgets that can form an embodiment of a leaflet anchor, according to an embodiment. [Figure 29] FIG. 29 is a cross-sectional view taken along line BB of FIG. 28, according to an embodiment. [Figure 30] FIG. 30 is a top view of one embodiment of sutures and pledgets that can form one embodiment of a leaflet anchor, according to an embodiment. [Figure 31] FIG. 31 is a diagram of one embodiment of the leaflet anchor shown in FIG. 30 showing sutures threaded through openings 31, according to an embodiment. [Figure 32] FIG. 32 is a side perspective view of a needle according to one embodiment of the present invention, according to an embodiment. [Figure 33] FIG. 33 is a perspective view of a pledget delivery handle according to one aspect of the present invention, according to an embodiment. [Figure 34A] FIG. 34A is a top rear perspective view of a suture management and stabilization system according to one aspect of the present invention, according to an embodiment. [Figure 34B] FIG. 34B is a top perspective view of the stabilization system and suture management system of FIG. 34A, according to an embodiment. [Figure 35] FIG. 35 is a side view of the stabilization system and suture management system of FIG. 34A, according to an embodiment. [Figure 36] FIG. 36 is a top view of the stabilization system and suture management system of FIG. 34A, according to an embodiment. [Figure 37] FIG. 37 is a close-up top view of the rear of the stabilization system and suture management system of FIG. 34A, according to an embodiment. [Figure 38] FIG. 38 is a close-up rear view of the stabilization system and suture management system of FIG. 34A, according to an embodiment. [Figure 39] FIG. 39 is a perspective view of the distal end of an alternative leaflet anchor deployment needle, according to an embodiment. [Figure 40] FIG. 40 is a schematic block diagram of a system for providing synchronized control signals based on detection of preselected points in the cardiac cycle, according to an embodiment. [Figure 41] FIG. 41 is a schematic block diagram of a trigger generator used in the system shown in FIG. 23, according to an embodiment. [Figure 42] FIG. 42 is a schematic block diagram of an actuator firing circuit used in the system shown in FIG. 40, according to an embodiment. [Figure 43] FIG. 43 is a schematic block diagram of an actuator unit used in the system shown in FIG. 40, according to an embodiment. [Figure 44] FIG. 44 illustrates waveforms of an ECG signal, a marker pulse, a trigger pulse, and a firing (fire) pulse in the system shown in FIG. 40, according to an embodiment. [Figure 45] FIG. 45 illustrates a touch sensitive monitor that may be used in the device shown in FIG. 40, according to an embodiment. [Figure 46] FIG. 46 is a schematic side view of a transcatheter mitral valve chordae tendineae repair system and a heart according to one aspect of the present disclosure, according to an embodiment. [Figure 47] FIG. 47 is a perspective cross-sectional view of a suture cutter mechanism according to one aspect of the present disclosure, according to an embodiment. [Figure 48] FIG. 48 illustrates the movement of pledget sutures and suture locks in a transcatheter mitral valve chordae repair system according to one aspect of the present disclosure, according to an embodiment. [Figure 49] FIG. 49 illustrates suture locking and suture movement according to one aspect of the present disclosure, according to an embodiment. [Figure 50] FIG. 50 illustrates suture locking and suture movement according to one aspect of the present disclosure, according to an embodiment. [Figure 51] FIG. 51 illustrates a suture lock, retention member, and anchor of a transcatheter mitral valve chordae repair system according to one aspect of the present disclosure, with the upper portion of the anchor extending along a portion of the lateral surface of the retention member, in accordance with an embodiment. [Figure 52]52 is a cross-sectional view of the transcatheter mitral valve chordae repair system shown in FIG. 51 with suture locks positioned within the retention members, according to an embodiment. [Figure 53] FIG. 53 is a diagram illustrating the orientation of a suture lock, retaining member, and anchor according to one aspect of the present disclosure, according to an embodiment. [Figure 54] FIG. 54 is a diagram illustrating suture locks and suture orientation in accordance with one embodiment of the present disclosure, according to an embodiment. [Figure 55] FIG. 55 illustrates an anchor, retention element, and suture lock of a transcatheter mitral valve chordae repair system according to one embodiment of the present disclosure, showing the anchor extending over the anchor hub, according to an embodiment. [Figure 56] FIG. 56 illustrates an anchor, retention element, and suture lock of a transcatheter mitral valve chordae repair system with the anchor advanced from the retention element into adjacent tissue, according to an embodiment. [Figure 57] FIG. 57 illustrates an anchor, retention element, and suture lock of a transcatheter mitral valve chordae repair system with the anchor advanced from the retention element into adjacent tissue, according to an embodiment. [Figure 58] FIG. 58 illustrates an anchor, retention element, and suture lock of a transcatheter mitral valve chordae repair system with the anchor advanced from the retention element into adjacent tissue, according to an embodiment. [Figure 59] FIG. 59 illustrates an anchor, retention element, and suture lock of a transcatheter mitral valve chordae tendineae repair system according to one embodiment of the present disclosure, showing an anchor pledget positioned between the suture lock and the anchor hub. [Figure 60] FIG. 60 illustrates an anchor, retention element, and suture lock of a transcatheter mitral valve chordae tendineae repair system according to one embodiment of the present disclosure, showing an anchor pledget positioned between the suture lock and the anchor hub. [Figure 61]FIG. 61 is a side view of a retaining member according to one aspect of the present disclosure, according to an embodiment. [Figure 62] FIG. 62 is a side view of an upper portion of a retention member according to one aspect of the present disclosure, according to an embodiment. [Figure 63] FIG. 63 is a diagram illustrating a retaining member having a densified portion for securing an anchor hub in accordance with an embodiment of the present disclosure. [Figure 64] FIG. 64 is a cross-sectional view of the socket shown in FIG. 63, according to an embodiment. [Figure 65A] FIG. 65A is a side perspective view of a socket according to one embodiment of the present disclosure, according to an embodiment. [Figure 65B] FIG. 65B is a top cross-sectional view of the socket shown in FIG. 65A, according to an embodiment. [Figure 66] FIG. 66 is a schematic illustration of an anchor, retention member, and suture lock according to one aspect of the present disclosure, according to an embodiment. [Figure 67] FIG. 67 is a diagram illustrating the orientation of an artificial chordae according to one embodiment of the present disclosure, according to an embodiment. [Figure 68] FIG. 68 is a side perspective view of a suture lock and lock driver mechanism in accordance with an embodiment of the present disclosure, according to an embodiment. [Figure 69] FIG. 69 is a side perspective view of a suture lock after fastening and initial disengagement of the lock driver mechanism and boot according to one aspect of the present disclosure, in accordance with an embodiment. [Figure 70] FIG. 70 is a side perspective view of the configuration of FIG. 69 with the lock driver and boot further apart in accordance with one aspect of the present disclosure, according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0058] U.S. Patent Application No. 15 / 858,671, filed December 29, 2017 (herein incorporated by reference in its entirety), discloses a method and system for implanting transvascular artificial chordae. One aspect includes advancing a catheter through the mitral valve into the left atrium and left ventricle, deploying a ventricular anchor from the catheter to the wall of the left ventricle, maintaining ventricular sutures attached to the ventricular anchor and extending proximally through the catheter, advancing the leaflet anchors to the mitral valve leaflets to secure the mitral valve leaflets to the leaflet sutures, the leaflet sutures extending proximally through the catheter, and securing the leaflet sutures to the ventricular sutures so as to extend above the coaptation margin and limit the extent of movement of the leaflets toward the left atrium. Specific aspects are further described herein.

[0059] The mitral valve approach is achieved via a standard transseptal approach to provide access to the left atrium. During this access, the first step involves securing a leaflet capture catheter to the mitral valve leaflets in a position determined to best correct regurgitation. Probing the leaflet surface from the superior vena cava surface advantageously provides immediate feedback regarding the optimal location for adding additional mitral valve chordae. In another embodiment of the present disclosure, the ventricular anchor is deployed first, followed by the leaflet anchor.

[0060] Referring to FIG. 1 , a ventricular anchor, such as a helical anchor 32, is deployed near the apex 20 of the left ventricle 24. While the helical anchor 32 is shown positioned near the apex 20, the anchor 32 may be attached at a point offset from the thin tissue at the apex or may be implanted in the thicker adjacent wall of the ventricle, such as between two papillary muscles. This allows the implanted neochordae construct (sutures, optional neopapillary muscles, and / or helical anchor) to be aligned along a longitudinal axis that is substantially parallel to or concentric with the natural path of the native chordae. In certain embodiments, the implanted neochordae construct is aligned along a longitudinal axis that is within 5°, 10°, or 15° of being parallel to the natural path of the native chordae and / or the natural path of adjacent native chordae. Additionally, although a helical anchor is shown, the anchor may have a different configuration for engaging cardiac tissue, and the helical configuration may be replaced by other tissue anchor configurations, including various barb, hook, or radially expandable structures known for engaging tissue.

[0061] 2A and 2B, a tissue anchor suitable for use as a ventricular anchor according to one embodiment of the present disclosure is shown. The anchor assembly 50 will be described primarily with respect to its current chordae tendineae repair application. However, the anchor may be used in many other applications where a soft tissue or bone anchor is desirable.

[0062] Anchor assembly 50 generally includes a coil 54. The coil may be made of a variety of materials, such as stainless steel or nitinol. Coil 54 extends helically between a proximal end 56 and a distal end 58. Distal end 58 includes a sharp tip or tissue-piercing point 59 and barbs 61 configured to resist back-rotation and separation of the coil from the tissue. Proximal end 56 of coil 54 is carried by (attached to or formed by) a hub 57, which will be described in more detail below.

[0063] An elongated core wire 62 extends distally from the hub 57 in the coil 54. The core wire 62 has a sharpened tissue-piercing distal end 64. The distal end 64 is located distal to the distal end 58 of the coil 54, allowing the sharpened distal end 64 to penetrate tissue upon contact and embed the coil in the desired tissue before rotation of the coil 54 is initiated. Engaging the end 64 before rotating the anchor stabilizes the anchor against lateral movement, allowing for single placement of the anchor 50 relative to the tissue and rotation of the coil 54 to engage the tissue without moving the anchor away from the desired target site, as will be understood by those skilled in the art. The proximal end of the core wire 62 may be attached to the hub 57 by a variety of methods, including soldering, brazing, adhesives, and / or mechanical interference, such as insertion into an opening in the exterior surface or sidewall of the hub 57.

[0064] A radiopaque depth marker 66 has an opening 68 and is carried axially movably on the core wire 62. A distal stop 70, such as a radially outwardly extending protrusion or annular ridge, is provided on the core wire 62 and spaced proximally from the sharpened distal end 64 to provide a core wire tip segment 72 distal to the stop 70. This prevents the marker 66 from interfering with the tissue anchoring function of the distal tip 64. The stop 70 functions to limit distal movement of the marker 66. The marker 66 may have a disk-like annular structure with a central opening to receive the core wire 62.

[0065] The coil spring 71 is concentric with the core wire 62 and biases the radiopaque marker 66 distally. The radiopaque marker 66 is thus held against the proximal face of the stopper 70. During use, the marker 66 contacts the tissue surface at the target attachment site. As the helical coil anchor 54 rotates and advances distally into tissue, the marker 66 moves proximally on the core wire 62 with the tissue surface, compressing the coil spring 71 until the marker 66 retracts proximally toward the hub when the tissue anchor is fully implanted. This allows for fluoroscopic visualization of the progression of the coil into tissue and the fully engaged end point of the implanted portion of the coil 54 relative to the target tissue by observing the changing distance between the marker 66 and a reference, such as the hub 57 or other radiopaque marker.

[0066] The hub 57 has a proximal connector for engagement with a rotation driver, as described elsewhere herein. In one embodiment, the connector has an opening, such as a hexagonal opening, for removably engaging a complementary surface feature on the distal end of the driver. A suture 74 is secured to the anchor assembly 50, for example, to the hub 57, the coil 54, or the core wire 62. In the illustrated embodiment, the suture 74 is attached to a cross pin 76. The cross pin 76 is inserted through one or more openings in the sidewall of the hub across the central hub passage. The suture may further include one or more radiopaque markers 82 spaced from the hub 57 and may extend proximally through the proximal connector and the central passage of the rotation driver.

[0067] A suture lock guide, such as a tubular sleeve 78, extends proximally from the hub 57 for at least about 2 mm, 4 mm, or 8 mm, but typically no more than about 5 cm or 2 cm, depending on the desired performance. In certain exemplary embodiments, a suture lock guide, such as a tubular sleeve 78, extends proximally from the hub 57 for at least 2 mm, 4 mm, or 8 mm, but typically no more than 5 cm or 2 cm, depending on the desired performance. The guide sleeve 78 may include (or be formed from) a flexible material, such as ePTFE. A radiopaque marker band 80 may be provided at the proximal end of the sleeve 78 and axially spaced from markers 82 on the sutures 74 to facilitate fluoroscopic visualization of the suture lock as it is advanced distally over the sutures 74. The marker band may be placed over the sleeve and everted to trap the ring, placing the marker band 80 between the inner and outer layers of the ePTFE sleeve.

[0068] The suture lock guide extends proximally from the illustrated sleeve or hub and may have various structures, such as alignment pins received in internal passages in the suture lock to maintain the orientation of the suture lock after removal from the deployment catheter. Because tension on the sutures is optimized while the suture lock is held in place by the deployment catheter, changes in the orientation of the suture lock after release from the catheter could affect the tension on the valve leaflets and adversely affect the therapeutic value of the implant. The suture lock guide functions to maintain a constant maximum distance between the ventricular anchor and the leaflet anchors both before and after deployment from the catheter. In this way, the maximum tension on the leaflet sutures (during systole) remains unchanged after the suture lock is locked, both before and after catheter removal.

[0069] The helical anchor assembly 50 is delivered by a ventricular anchor delivery subsystem 300. Figures 2C-2E illustrate the ventricular anchor delivery subsystem 300 and its components. Figure 2C is a perspective view of the distal end of subsystem 300. Figure 2D is a perspective view of the proximal end of subsystem 300. Figure 2E is a partial exploded view of the distal end of subsystem 300.

[0070] The subsystems 300 may be delivered through the delivery catheter 100, which may access the left atrium by conventional techniques, such as an atrial trans-septal puncture. As the various subsystems are placed and removed from the delivery catheter 100, the delivery catheter 100 may be maintained in a substantially constant position throughout the procedure. For example, the distal end of the delivery catheter 100 may be positioned in the left atrium. In other examples, the distal end of the delivery catheter 100 may remain positioned in the left atrium throughout the procedure.

[0071] 2C-2E, ventricular anchor delivery subsystem 300 includes outer sheath 304, a driver (including shaft 307 and head 306), anchor hub 308, and anchor 302. The anchor is a helical anchor 302, and driver head 306 is configured to rotate helical anchor 302. Helical anchor 302 may have an inner diameter configured to be disposed over the outer diameter of anchor hub 308. Helical anchor 302 may be securely secured to anchor hub 308 by an interference fit, other frictional engagement, soldering, or other known attachment techniques. Anchor hub 308 may remain implanted along with helical anchor 302.

[0072] The anchor hub 308 may have an internal passageway (lumen) disposed substantially along the central axis of the anchor hub 308 for receiving the suture 74 ( FIG. 2A ) and attaching the suture 74 to the helical anchor 302. In some embodiments, the suture 74 may have an attachment element (e.g., a knot, tie, or washer) having a diameter sized to prevent the suture 74 from being pulled proximally through the internal passageway of the anchor hub 308. For example, the suture 74 may be tied distally of the internal passageway. In some embodiments, the suture 74 may be tied to the anchor hub 308 (e.g., wrapped through the internal passageway around a structure such as an exterior surface or the cross pin 76 shown in FIG. 2B and tied to itself).

[0073] Helical anchor 302 may include a distal section of windings and a proximal section of windings. The proximal sections of windings may be spaced closer together than the distal sections of windings and may be configured to secure helical anchor 302 to anchor hub 308. The distal sections of windings may be spaced further apart than the proximal sections of windings and may be configured to be inserted into ventricular tissue. Anchor hub 308 may have an enlarged cross-section at its proximal end configured to abut helical anchor 302 and / or prevent helical anchor 302 from advancing proximally beyond the proximal end of anchor hub 308. Other helical anchors, such as those described elsewhere herein, may be configured for use with ventricular anchor delivery subsystem 300 described herein.

[0074] The proximal face of the helical anchor 308 may have a recess for receiving the extension portion 306' of the driver head 306. The recess may be non-circular (e.g., rectangular or polygonal, such as a hexagon) so as to be configured to transfer torque from the driver to the anchor hub 308 upon rotation of the driver. The recess may be disposed about a central interior passageway of the anchor hub 308.

[0075] In other embodiments, the anchor hub 308 may have an extension and the driver 306 may have a complementary recess. The driver head 306 may be cylindrical with an opening or distally facing post having complementary structure for rotatably engaging a corresponding component on the anchor. The driver head 306 may be fixedly coupled to the drive shaft 307. The driver may have a central internal passageway through the drive shaft 307 and driver head 306 configured to receive the suture 74. The central internal passageway of the driver may be configured to align with the central internal passageway of the anchor hub 308. The drive shaft 307 may be received within the guide shaft 305. The diameter of the driver head 306 is larger than the inner diameter of the guide shaft 305. The outer sheath 304 may be sized to receive the guide shaft 305, the driver head 306, the anchor hub 308, and the helical anchor 302.

[0076] The outer sheath 304 is advanced through the delivery catheter 100 into the left ventricle and delivered proximal to the ventricular attachment site. In some embodiments, the outer sheath 304 may be advanced without the delivery catheter. In some implementations, the helical anchor 302 may be hidden within the outer sheath 304 until the outer sheath 304 is positioned at the ventricular attachment site and pushed distally through the outer sheath 304 or retracted proximally to expose the helical anchor 302. The helical anchor 302 may be positioned to contact ventricular tissue. Rotation of the drive shaft 307 rotates the driver head 306, anchor hub 308, and helical anchor 302, thereby threading the ventricular anchor 302 into the ventricular tissue. Rotation of driver 309 advances driver 309 , anchor hub 308 and helical screw 302 distally and axially relative to outer sheath 304 .

[0077] As shown in FIG. 2D, drive shaft 307 is manually rotated by a user using drive handle 312. As shown in FIG. 2D, the proximal end of ventricular anchor delivery subsystem 300 includes hemostatic valves 314, 316. A first hemostatic valve 314 may be located distal to drive handle 312 and may provide access to guide shaft 305. A second hemostatic valve 316 may be located proximal to drive handle 312 and may provide access to a central interior passageway of the driver. Ventricular anchor sutures (not shown) may extend through second hemostatic valve 316.

[0078] In some implementations, the insertion portion 306' of the driver head 306 and the recess in the anchor hub 308 can have a frictional engagement that temporarily holds the two components together. The frictional engagement is released when the helical anchor 302 is inserted and reaction force from the ventricular tissue retracts the driver proximally. In some implementations, proximal tension on the suture 74 creates an engagement force between the proximal hub 308 and the driver head 306, which is released upon retraction of the driver 309. The driver head 306 may be retracted proximally into the outer sheath 304 before the outer sheath 304 is retracted into the delivery catheter 100.

[0079] The non-implanted components of ventricular anchor delivery subsystem 300 may be removed from delivery catheter 100, after which the subsystem may be deployed on delivery catheter 100 to complete implantation of the neochordae tendineae. In an alternative embodiment, subsequent subsystems, such as ventricular anchor delivery subsystem 300 and leaflet anchor delivery subsystem 330, may be deployed simultaneously within delivery catheter 100, or in one configuration, both the tissue anchor and the leaflet anchor may be pre-loaded onto the delivery catheter. In other embodiments, implantation of the ventricular anchor may be performed in a different order (e.g., after implantation of the leaflet anchor). The ventricular anchor delivery components may be retracted proximally beyond the proximal end of suture 74, which may remain extending through delivery catheter 100 to ventricular anchor 302.

[0080] In certain embodiments of the present disclosure, it may be desirable to provide a second anchor to prevent reverse rotation of the helical coil 54 of the ventricular anchor 32 after implantation, which could result in dislodgement of the helical coil 54 from the attachment site. Generally, the second anchor is deployed from a first configuration, such as for attachment and transluminal guidance of the first helical anchor, to a second deployed configuration that engages tissue and prevents dislodgement of the helical anchor 54 from the attachment site.

[0081] In certain embodiments, the second anchor may be automatically deployed into the second configuration upon full engagement of the first helical anchor. Alternatively, the second anchor may be deployed by manual manipulation of the pusher control or distal advancement by the attending physician or clinician. The pusher may be in the form of a tubular body axially movably mounted on the anchor driver. Alternatively, the pusher may include an anchor driver. In such an example, the anchor driver may have an engaging surface structure, such as a ratchet, that cooperates with a complementary surface structure on the radially inwardly facing surface of the second anchor assembly. The anchor driver may be retracted proximally without affecting the second anchor, but subsequent distal advancement of the anchor driver deploys the second anchor. Alternatively, the pusher may include a suture locking catheter, as described below.

[0082] The second anchor described above with reference to Figures 2F and 2G may be used independently and / or in conjunction with the features and aspects of the ventricular anchor 32 described herein with respect to the embodiment described with reference to Figures 2A-2E.

[0083] 2F and 2G show one embodiment of a ventricular anchor 32 that includes a second anchor 110. In the illustrated embodiment, the second anchor 110 has at least a first tine 112 extending between a proximal end 114 and a sharp distal end 116. The tine 112 may be supported by a support 118, such as by connection to the proximal end 114. The support 118 facilitates axial advancement of the tine 112. In the illustrated embodiment, the support 118 comprises an annular structure, such as a ring 122, having an opening 120. The opening 120 is configured to axially moveably receive an anchor driver (not shown) or other tubular structure or component that may be part of the anchor deployment system.

[0084] Hub 57 includes at least one first branch guide 124, such as an opening or passageway, for axially and movably receiving first branch 112. First branch guide 124 may include a deflection surface for deflecting branch 112 at a launch angle that is angled radially outward in the distal direction. The launch angle measured at the exit from branch guide 124 ranges from about 30° to about 45°, and in other embodiments, from about 35° to about 40° from the central longitudinal axis of the anchor. In certain exemplary embodiments, the launch angle measured at the exit from branch guide 124 may be within the range of 30° to 45°, and in some embodiments, within the range of 35° to 40°, from the central longitudinal axis of the anchor.

[0085] As an alternative to or in addition to a deflection surface, the tines may be pre-biased radially outward so as to angle outward as they advance from the tine guide 124. Distal advancement of the first tine 112 advances the tine through the first tine guide, distally extending the tine 112 radially outward to expose at least about 1 mm, or 2 mm, or 3 mm, or 4 mm, or more, of its tine length, depending on the desired performance. In certain exemplary embodiments, distal advancement of the first tine 112 advances the tine through the first tine guide, distally extending the tine 112 radially outward to expose at least about 1 mm, or 2 mm, or 3 mm, or 4 mm, or more, of its tine length, depending on the desired performance. When measured perpendicular to the longitudinal axis, the distal tips 116 of the fully deployed branches are spaced at least about 1 mm, or 2 mm, or 3 mm, or 4 mm, or more, from the outer surface of the helical coil 54. In certain exemplary embodiments, when measured perpendicular to the longitudinal axis, the distal tips 116 of the fully deployed branches are spaced at least about 1 mm, or 2 mm, or 3 mm, or 4 mm, or more, from the outer surface of the helical coil 54. The distal tips 116 when fully deployed may be spaced laterally from the helical coil by at least about 50%, or 75%, or 100%, or more of the outer diameter of the helical coil. In certain exemplary embodiments, the distal tips 116 when fully deployed may be spaced laterally from the helical coil by at least 50%, or 75%, or 100%, or more of the outer diameter of the helical coil.

[0086] The tines 112 may be formed from or include any of a variety of materials that have sufficient structural integrity to resist rotation and / or retain a bias, such as stainless steel or nitinol. The tines 112 may be flat ribbon or round wire, and in one embodiment, are made from 0.016 inch stainless steel round wire.

[0087] Distal advancement of first branch 112 may be achieved by applying distal pressure to support 118, such as by a catheter or second anchor deployment pusher advanced over suture 74 and / or an anchor driver, as described elsewhere herein. Alternatively, second anchor 110 may be deployed by distally advancing a suture lock over the suture into contact with support 118, such that support 118 is advanced distally and constrains support 118 between hub 57. In this manner, the suture lock may function as a second anchor lock to prevent or inhibit backout of the second anchor from the deployment site.

[0088] A second prong 126 may be provided that extends through a second prong guide 128 and connects to the support ring 122. Three, four, or more prongs may be provided depending on the desired performance of the second anchor system. In the illustrated embodiment, two prongs are shown spaced approximately 180° apart around the circumference of the helical anchor. In an embodiment including three prongs, the prongs are equidistantly spaced approximately 120° apart.

[0089] As shown, branch guides 124, 128 can guide branches 112, 126 through the material (fiber) of the tubular suture anchor guide. The sutures may have openings aligned with the branch paths, or the branches may penetrate the material upon deployment. The branch exit paths can be moved distally as needed, so that the branches extend axially through the hub and into the helical coil and exit laterally between the windings of two adjacent coils spaced apart from one another. The branches and / or supports 118 may include radiopaque markers or materials to allow fluoroscopic confirmation of complete deployment.

[0090] The use of one or more second anchors 110 can increase the anchor torque resistance of the helical coil 54, inhibiting or preventing back-rotation of the helical coil 54 of the ventricular anchor 32 after implantation. Such back-rotation after implantation can cause the helical coil 54 to become dislodged or loose from the site of application. In some embodiments, the second anchors 110 can increase the torque resistance of the ventricular anchor 32 by at least 2, 4, 6, 8, or 10 times compared to use of the ventricular anchor 32 without the second anchors 110. In certain embodiments, the addition of one or more second anchors 110 can increase torque resistance by 2-10 times compared to use of the ventricular anchor 32 by itself, and in certain embodiments, one or more second anchors can increase torque resistance by 2-5 times. In such embodiments, multiple prongs of the second anchor may be used, and in certain embodiments, 2, 3, 4, or 5 may be used, which may be in the form of prongs 112, 126 as described above. In some embodiments, the torque resistance using one or more prongs of the second anchor 110 may be greater than 2 N / cm. In some examples, the torque resistance of one or more prongs of the second anchor 110 combined may be between at least 2 N / cm and 5 N / cm.

[0091] Additionally, the use of one or more second anchors 110 can increase the torque stiffness of the helical coil 54 to prevent or inhibit wobbling or slippage, which can also prevent the helical coil 54 of the ventricular anchor from becoming dislodged from its attachment site. For example, the second anchor 110 can increase torque stiffness by at least 2, 4, 6, 8, or 10 times compared to the use of a ventricular anchor without the second anchor 110, and in certain embodiments, can increase torque stiffness by 2 to 10 times, and in certain embodiments, 3 to 8 times compared to the ventricular anchor without the second anchor 110. In such embodiments, one or more second anchors can be used, and in certain embodiments, two, three, four, or five second anchors 110 are used, and in certain embodiments, the second anchors can be in the form of branches 112, 126, as described above. In certain embodiments, the torque resistance provided by the one or more second anchors 110 can be greater than 0.02 N-cm / deg, and in some examples, the torque resistance provided by the one or more second anchors 110 can be between 0.01 N-cm / deg and 0.03 N-cm / deg.

[0092] In some examples, each of the one or more branches of the second anchor 110 can have a length of at least 5 mm as measured from the hub 57. In some examples, each of the one or more branches of the second anchor 110 can have a length of 1 mm to 8 mm, in particular embodiments, a length of 4 mm to 7 mm, and in particular embodiments, a length of 5 mm. The width between any two branches of the second anchor 110 can be approximately 12 mm. In some examples, the width between any two branches can be 5 mm to 15 mm. The length and width of the branches advantageously allow the branches of the second anchor 110 to extend into the pericardial cavity without penetrating the ventricular wall, while still providing sufficient torque resistance and stiffness. In some examples, each of the one or more branches of the second anchor 110 can have a length of at least 5 mm as measured from the hub 57. In some examples, each of the one or more prongs of the second anchor 110 can be 1 mm to 8 mm in length, in particular examples, 4 mm to 7 mm in length, and in particular examples, 5 mm in length. The width between any two prongs of the second anchor 110 can be approximately 12 mm. In some examples, the width between any two tines can be 5 mm to 15 mm. The length and width of the tines can advantageously allow the prongs of the second anchor 110 to extend into the pericardial space without penetrating the ventricular wall, while still providing sufficient torque resistance and stiffness.

[0093] The thickness of each branch can be approximately 0.3 mm. In some examples, the thickness of each branch can be between 0.1 mm and 0.5 mm. This thickness of the branches can provide adequate bending or yielding as the branches advance.

[0094] Additionally, the angle of each branch from the centerline of the helical coil 54 can be approximately 40°. In some instances, the angle of each branch from the centerline of the helical coil 54 can be between 25° and 60°. This angle can advantageously be extended to provide the desired torque resistance and stiffness while avoiding perforation of the ventricular wall. This can also provide the desired orientation of each branch toward the mitral valve when the anchor is placed obliquely against the ventricular wall.

[0095] The end of each prong may optionally be coined along its length, which can prevent the second anchor from being pulled too far back into hub 57 by capturing the coined portion distal to the respective prong guide 124 or hole in hub 57 through which the prong passes.

[0096] 3-6 illustrate the deployment of the leaflet anchor. Referring to FIG. 3, the ventricular anchor 32 is deployed and tethered to the catheter 100 by the ventricular anchor sutures 74, and the ventricular anchor subsystem is removed. The leaflet anchor is carried within a needle 338 pointed toward a target site on the atrial side of the valve leaflet. The needle 338 is advanced axially and reciprocally within the catheter 100, such as a tubular sleeve or leaflet anchor catheter 332 advanceable through the catheter 100. Needles and needle drivers are further described below.

[0097] As shown in Figure 3, in the illustrated configuration, the needle can be passed through the leaflet from the atrium to the ventricle and then the pre-loaded suture can be advanced into the ventricle. The suture can then be used to fold the pledget against the ventricular side of the leaflet and secure the suture to the leaflet, as shown in Figure 4. The pledget thus forms a radially expandable leaflet anchor. Radially expandable leaflet anchors having other configurations may also be used in certain embodiments.

[0098] The leaflet anchors and sutures may be used in combination with ventricular anchor sutures and suture locks to effectively create new mitral valve chordae as shown in Figure 5. As previously mentioned, the leaflet anchors and sutures may be used in combination with the transvascular artificial chordae implantation method and system disclosed in U.S. Patent Application No. 15 / 858,671 (hereby incorporated by reference in its entirety), which discloses various embodiments of ventricular anchor sutures and suture locks.

[0099] The leaflet anchor deployment subassembly includes a temporary anchor for capturing and stabilizing the valve leaflet during passage and advancement of the needle tip 338 through the target. As shown in FIG. 3 and the figures, the distal end 400 of the delivery tube 332 or other system component includes a temporary tissue anchor, such as a helical tissue anchor 402. The temporary anchor 402 may be similar to the ventricular anchor, except that it does not have a distal turn (barb), as it is intended only to momentarily engage the valve leaflet. Thus, the anchor 402 includes a helical element 406 terminating in a distal tip 408.

[0100] In use, the distal tip 408 is placed at a target site on the surface of the valve leaflet, and the helical element 406 is rotated about or about the axis to engage and penetrate the leaflet. Similar to the method described for the ventricular anchor with reference to Figures 2A and 2B, the needle tip 338 may optionally engage the leaflet prior to rotation of the helical element 406 and be used to stabilize the anchor against movement away from the target site in response to rotation.

[0101] Following engagement of the helical element 406 to capture the leaflet from the atrial side and secure the leaflet to the catheter, the needle is advanced distally through the central internal passage defined by the helical element 406 and advanced completely through the leaflet, causing the needle tip 338 to protrude from the ventricular side of the leaflet, as shown in Figure 4. An anchor deployment actuator, such as a pusher extending through the needle, can be utilized to deploy the anchor from the needle into the ventricle using the anchor deployment actuator.

[0102] Referring to FIG. 5 , the leaflet anchor may be a pledget 340, as described elsewhere herein. The pledget 340 may be attached or bonded to the distal end of a leaflet anchor suture 344. The pledget may comprise a soft and / or flexible material, such as a fiber (woven fabric, cloth). The suture 344 may extend through the needle 336. The pledget 340 may be folded or compressed to a configuration including a reduced radial cross-section so that it may be placed within the needle 336 for delivery (described below with reference to FIGS. 8 and 10 ). As shown in FIG. 5 , the pledget 340 may expand from a reduced cross-section to a larger radial cross-section upon deployment from the distal end of the needle tip 338. In some embodiments, the pledget 340 is pushed through the needle 336 via a push wire or release wire (not shown). Upon delivery through the needle tip 338, proximal retraction of the leaflet sutures 344, as shown in FIG. 6, causes the leaflet anchor to collapse axially into a radially expanded configuration, thereby preventing the leaflet anchor from retracting through the leaflet puncture and securing the leaflet sutures 344 to the leaflet, as shown in FIG. 7.

[0103] 6A-6D schematically illustrate a pledget 340 connected to the distal end of a leaflet suture 344. The pledget 340 includes two wings 341, 342 that are rolled / folded (e.g., clockwise or counterclockwise) about the longitudinal axis of the pledget 340 to form a reduced cross-sectional shape. In some embodiments, the leaflet suture 344 may be integrally formed with the pledget 340. To form a collapsible or foldable structure, as shown in FIG. 6A, the suture 344 extends distally through the pledget, loops at the distal end of the pledget, returns proximally, and threads through one or more openings (e.g., two openings, three openings, four openings, etc.) formed in the pledget 340. In some embodiments, the openings are aligned along the center of the pledget 340.

[0104] The openings may extend through the pledget 340 and the portions of the embedded portions of the sutures 344 that are integral with the pledget 340. The embedded portions of the sutures 344 are at least partially flattened within the pledget 340. In some embodiments, the openings may be located substantially near the center of the pledget (e.g., immediately to the left or right of the embedded sutures 344 or alternating between the left and right sides of the sutures 344). When deployed, the sutures 344 are effectively bonded to the distal end of the pledget 340 (e.g., the sutures 344 loop back to where they were inserted between the pledget sheets).

[0105] 6B-6D schematically illustrate examples of pledgets described elsewhere herein. FIG. 6B schematically illustrates a pledget 340 formed by attaching the distal end of a stitch 344 (shown in dashed lines) between two flat sheets, representing the sheets for the left and right wings 341, 342. FIG. 6C is a cross-sectional view of the pledget 340 along axis BB in FIG. 6B. In some embodiments, the stitch 344 is inserted between the two sheets (e.g., substantially in the center of the sheets) and pressed and / or laminated (e.g., under heat and / or pressure) to bond the three components together. At least one layer may be partially sintered. The stitch 344 may be flattened and / or densified to improve the stitch's resistance to tearing or ripping. The sheets may be flat polytetrafluoroethylene (PTFE) sheets (e.g., thin, uncured expanded PTFE (ePTFE) sheets) or any suitable material. In one embodiment, the leaflet sutures 344 may be arranged between the sheets in alternative configurations, such as a zigzag or S-shape. Figure 6D shows the pledget 340 of Figure 6B. The pledget 340 has multiple openings 343 through the proximal tails of the sutures 344.

[0106] In some embodiments, one or more openings 343 are formed through the pledget in various configurations to form a collapsible structure configured to secure the sutures 344 against the leaflets of the mitral valve, as described elsewhere herein. FIG. 6D shows alternating openings 343 on the back side of the sutures 344. In some embodiments, the openings 343 may be formed on the same side of the sutures 344 (e.g., in wing 341 or wing 342). In some embodiments, the openings 343 may be formed through the sutures 344. The openings 343 may be aligned along the center of the pledget 340. The openings 343 may be aligned along the length of the sutures 344 (e.g., forming a straight line). The sutures 344 are at least partially flattened between two opposing sheets, which facilitates placement of the openings 343 through the sutures 344. Various combinations of openings 343, including the positioning described above, may be used.

[0107] The pledget 340 may be formed so that the wings 341, 342 are approximately the same size, or they may be formed so that they are unequal in size. As the leaflet sutures 344 are retracted proximally, the pledget 340 folds like an accordion, as shown in FIG. 6A . The pledget 340 may be configured with a generally planar proximal surface that is substantially perpendicular to the longitudinal axis. This configuration may allow the sutures 344 to be easily secured to the leaflets. Once the leaflet sutures 344 are secured to the leaflets, the leaflet anchor delivery subsystem 340 is withdrawn from the delivery catheter 100. The leaflet anchor delivery element may be retracted proximally over the proximal end of the sutures 344. The sutures 344 continue to extend through the delivery catheter 100 to the leaflet anchor 340, alongside the ventricular anchor sutures 74.

[0108] Figures 8-10 illustrate the leaflet anchor delivery subsystem 330 and its components. Figure 8 is a perspective view of the distal end of the subsystem 330. Figure 9 is a perspective view of the proximal end of the subsystem 330. Figure 10 is an exploded view of the distal end of the subsystem 330.

[0109] As shown in Figures 8 and 10, leaflet anchor delivery subsystem 330 may include an outer delivery tube 332. Tube 332 may optionally have a flex section and may be configured to be manipulable by an operator through proximal retraction of one or more pull wires (not shown) along various sides of flex tube 332. The operator may control the bending of the flex tube via a knob 352 or lever or other actuation mechanism located on a handle 350 at the proximal end of leaflet anchor delivery subsystem 330, as shown in Figure 9.

[0110] An inner tubular shaft or needle 336 may extend through the delivery tube 332, terminating in a distal end including a needle point 338. The inner needle 336 may comprise a hypotube, extruded or braided tube or catheter that is flexible enough to conform to the shape of the optional flex tube 332. The needle tip 338 may be attached to the distal end of the flexible shaft 336. A flexible jacket 333 may surround the flex tube 332 and the delivery shaft 334.

[0111] As shown in FIG. 9 , the proximal end of the inner tubular shaft 336 may be connected to a needle handle 354. The needle handle 354 may include a hemostatic valve 356. The leaflet suture 344 may be inserted through the valve 356. The valve 356 may be a Tuohy-Borst valve. The needle handle 354 may have an additional port 358 for accessing the internal passage of the inner flexible shaft 336. The needle handle 354 may be positioned proximally relative to the handle 350 such that the inner flexible shaft 336 extends through the handle 350 and into the internal passage of the delivery shaft 334. The handle 350 may include a hemostatic valve for receiving the inner flexible shaft 336 and sealing the internal components of the handle, including the opening to the delivery shaft 334, from the surrounding environment.

[0112] The needle tip 338 may be extendable or retractable by extending the needle handle 354 toward or retracting the needle handle 354 from the handle 350. Distal advancement of the needle 336 may be achieved by manually advancing the handle 354. Alternatively, distal advancement of the needle may be assisted by a mechanical or electromechanical mechanism to achieve relatively high speed, short stroke length distal advancement.

[0113] When pressure is applied to the valve leaflet as the needle tip 338 is extended distally beyond the tube 332, the needle tip 338 punctures the leaflet and extends to the opposite side of the leaflet (e.g., the atrial side), as shown in Figure 4. This pressure can be applied by extending the needle tip 338 and / or by retracting the entire delivery device 330 with the needle tip 338 in the extended position.

[0114] The ventricular anchor sutures 74 and leaflet anchor sutures 344 may be joined together under tension to form a neochordae implant, or two sections of the neochordae implant may be joined together, with neochordae extending between the ventricular anchor 302 and the leaflet anchor 340 across the atrial side of the coaptation edges of the leaflets. The overall length of the neochordae can be adjusted by pulling one or both sutures 74, 344 proximally before engaging the suture lock 376 so that the appropriate tension is applied to the leaflets and maintained by the ventricular anchor 302. The sutures 74, 344 can continue to extend proximally through the delivery catheter 100 to a location outside the body. In some embodiments, the proximal ends of the sutures 74, 344 can be fed into a handle or proximal portion of the suture lock delivery system 370 to facilitate placement of the suture lock and cutting of the sutures 74, 344. In some embodiments, the proximal end may be free or may be attached or secured to other means.

[0115] FIG. 11 illustrates the advancement of the suture lock 376 over the ventricular anchor sutures 74 and leaflet sutures 344. The suture lock delivery subsystem 370 is advanced through the delivery catheter 100, and a tubular pusher catheter 372 pushes the suture lock 376 distally along the sutures 74, 344. Once the suture lock 376 reaches the ventricle, it continues to be pushed along the ventricular sutures 74 by retracting the sutures 74 proximally, while allowing the leaflet sutures 344 to be fed distally through the catheter if the suture lock 376 needs to be advanced distally to the ventricular anchor. As discussed further below, FIG. 12 illustrates the final configuration in which the leaflet anchor and ventricular anchor are joined to form the artificial chordae tendineae. The proximal tails of the two sutures are cut, and the catheter is retracted proximally from the ventricle through the mitral valve.

[0116] Figures 13-14 illustrate the suture lock delivery subsystem 370 and its components. Figure 13 is a perspective view of the distal end of the subsystem 370. Figure 14 is a perspective view of the proximal end of the subsystem 370. Figure 15 is a partial exploded view of the distal end of the subsystem 370. Figure 16 is a perspective view of the distal end of the cutting assembly. Figures 17 and 18 are side views of the cutting assembly portion of the subsystem 370. Figure 19 is a side view of the suture lock 376 and the distal end of a torque driver 388 configured to engage the suture lock 376. Figures 20 and 21 show the proximal and distal ends of the suture lock 376, respectively.

[0117] The suture lock delivery subsystem 370 may be configured to advance (e.g., slide) a suture lock 376 over both sutures 74, 344 (or three, four, or additional sutures) to secure them. The sutures 74, 344 may each be retracted proximally relative to the suture lock 376 to tension the sutures 74, 344 and adjust the length of each suture 74, 344 between the suture lock 376 and each tissue anchor 302, 340. Once the tension and length of the neochordae implant are optimized, the suture lock 376 is locked to fix the length of the sutures 74, 344 so that the sutures 74, 344 cannot move relative to the suture lock 376. The sutures 74, 344 may then be cut at a point proximal to the suture lock 376. The sutures 74, 344 may be cut by the same suture lock delivery subsystem 370 that delivers the suture lock 376. In other embodiments, a separate cutting device is inserted into the delivery catheter 100 after the suture lock is locked in place.

[0118] The suture lock allows for adjustment of the suture by advancing one or more sutures through the lock, and can lock the suture with sufficient clamping force to prevent the ePTFE suture from slipping from the suture lock under normal use conditions (e.g., withstands a tension of at least about 60% or 80% or more of the suture's breaking strength without slipping). In certain exemplary embodiments, the suture lock allows for adjustment of the suture by advancing one or more sutures through the lock, and can lock the suture with sufficient clamping force to prevent the ePTFE suture from slipping from the suture lock under normal use conditions (e.g., withstands a tension of at least about 60% or 80% or more of the suture's breaking strength without slipping). The lock can be released and retightened to readjust the tension on the mitral valve leaflets until the desired result is achieved. The tightening tool can then be removed, leaving the suture lock.

[0119] The suture lock 376 may be advanced along the suture by a retainer catheter 373. The distal end of the retainer catheter 373 may be coupled to a retainer element 377 ( FIG. 15 ). The retainer element may include a flange 371 or other mechanical feature configured to engage the suture lock 376. For example, the flange 371 may be inserted into a recess at the proximal end of the suture lock 376. In some embodiments, to remove the retainer catheter 373 from the suture lock 376, the retainer catheter 373 may be rotated and / or moved in a direction substantially perpendicular to the axial direction of the retainer catheter 373.

[0120] The sutures 74, 344 extend from their respective tissue anchors through the suture lock 376, entering through a distal opening 395 on the distal face of the suture lock 376, shown in FIG. 21 , and exiting through a proximal opening 394 to the suture track on the proximal face of the suture lock 376, shown in FIG. 20 . The sutures 74, 344 may extend through a channel in the cutter head 375 proximal to the suture lock 376, along the outside of the retainer catheter 373, and through the delivery catheter 100. The cutter head 375 may be coupled to the distal end of the cutter catheter 372. The retainer catheter 373 may extend within the interior passageway of the cutter catheter 372 such that the two catheters 372, 373 may be extended (expanded) or retracted relative to each other.

[0121] Once the sutures 74, 344 are locked within the suture lock 376, the proximal ends of the sutures 74, 344 may be severed adjacent the proximal face of the suture lock. The sutures 74, 344 may be severed by advancing a cutter catheter 372 coupled to a cutter head 375 toward the proximal face of the suture lock 376. As shown schematically in FIGS. 17-18 , as the cutter head 375 advances along the retainer catheter 373 toward the retainer element 377, the cutter head brings the sutures 74, 344 into proximity with a cutting blade 379 disposed on the retainer element 377. The cutter head 375 is configured to advance over the retainer element 377 such that the channel in the cutter head 375 that holds the sutures 74, 344 is progressively occupied by the blade 379. As the blade 379 is forced into the channel of the cutter head 375, the blade 379 shears the sutures 74, 344. Applying proximal tension to the sutures 74, 344 facilitates severing the sutures 74, 344. In other embodiments, different actuations (e.g., rotation of the cutting catheter) may be configured to sever the sutures 74, 344.

[0122] In some implementations, more than one suture may be used and may be locked within the suture lock 376 and cut by the suture lock delivery subsystem 370 in the same manner. In some examples, advancement of the cutter head 375 over the retainer element 377 facilitates release of the retainer catheter 373 from the suture lock 376. For example, the cutter head 375 may be advanced to a distal position that stabilizes the suture lock 376, releasing the retainer catheter 373 axially and / or rotationally from the suture lock 376.

[0123] FIG. 19 shows a side view of an exemplary suture lock 376 (shown with the outer casing / shell removed). As described elsewhere herein, a suture passes through the suture lock 376 from its distal end to its proximal end. The suture lock 376 includes a screw 382 configured to advance a push wedge 384 distally or retract a push wedge 384 proximally, depending on the direction of rotation of the screw. The screw 382 can be rotated by a torque shaft 388. The torque shaft 388 has a driver head configured to mate with a recess 381 (e.g., a polygonal recess or other non-circular recess, as shown in FIG. 20) located at the proximal end of the suture lock 376, such that rotation of the torque shaft 388 rotates the screw 382. The torque shaft 388 extends through an internal passageway of the retainer catheter 373. The torque shaft 388 is rotated at its proximal end by a knob 398 or other actuation mechanism located at the proximal end of a subsystem handle 396. The handle 396 has a hemostatic valve 397. In some implementations, the sutures 311, 344 pass through the hemostatic valve 397.

[0124] Advancement of push wedge 384 by torque shaft 388 causes a ramp or inclined surface 386 to gradually compress one or more springs, such as spring pin 388. The springs urge the clamp upward to open the suture path until rotation of torque shaft 388 forces it closed. Compression of spring(s) 388 forces clamp 390 downward onto sutures 311, 344, compressing sutures 311, 344 between two opposing surfaces. In some embodiments, clamp 390 and opposing surface 392 may have notched surfaces configured to mate with one another in discrete increments. The mating notched surfaces enhance friction and, in some embodiments, provide mechanical interference to hold sutures 311, 344 between the opposing surfaces so that sutures 311, 344 cannot be pulled proximally or distally from suture lock 376. In some embodiments, the tightening can be reversed by rotating the torque shaft in the opposite direction.

[0125] Once the suture lock is properly positioned over the sutures 74, 344 and locked in place, the sutures 74, 344 may be cut as described elsewhere herein. Figure 12 shows retraction of the suture lock delivery subsystem 370 after the sutures 74, 344 have been cut. Once the suture lock delivery subsystem 370 has been removed from the delivery catheter 100, the delivery catheter 100 may be withdrawn from the body.

[0126] Collapsible Anchor Delivery Sheath Depending on the configuration of anchor assembly 50, coil 54, and / or tubular sleeve 78, in certain embodiments, the outer profile of the deployed anchor assembly 50 may be larger than the inner diameter of the delivery catheter 100 and / or introducer sheath. Accordingly, in certain embodiments, as shown in FIGS. 22A-E , the ventricular anchor delivery subsystem 300 may be modified to have a collapsible anchor delivery sheath 404 such that the ventricular anchor delivery subsystem 400 provides protection and support for the anchor assembly 50, coil 54, and / or tubular sleeve 78 during delivery and fits the inner diameter of the delivery catheter 100. In this manner, the collapsible anchor delivery sheath 404 may be collapsed to a smaller diameter while the sheath 404 is retracted into the delivery catheter 100. The collapsible delivery sheath 404 may also be configured to secure the anchor assembly 50 during delivery, for example, to prevent the anchor assembly 50 from becoming dislodged from the delivery sheath 404 due to the beating ventricle or other movements or shapes encountered during introduction and deployment. Additionally, in certain embodiments, the delivery sheath 404 is sufficiently kink-resistant to resist the movement of the beating ventricle when the coil 54 of the anchor assembly 50 engages the heart wall. As described below, the sheath 404 may include a radiopaque tip for detection. The delivery sheath 404 in certain embodiments may have an inner diameter sufficient to retain the coil 54 and tubular sleeve 78, yet an outer diameter small enough to fit within the delivery catheter 100 or introducer sheath. In certain embodiments, the anchor delivery sheath 404 is collapsible so that the sheath 404 can be pulled through a narrower constriction of the delivery catheter 100 without excessive force or breaking as the anchor assembly 50 is delivered. In certain embodiments, the anchor delivery sheath 404 is adapted to transition in diameter from the inner diameter size of the delivery catheter 100 (e.g., approximately 9 Fr in some embodiments) to a second, larger size required to accommodate the anchor assembly 50 (e.g., approximately 19 Fr in some embodiments).In certain embodiments, the anchor delivery sheath 404 is adapted to transition in diameter from the inner diameter size of the delivery catheter 100 (e.g., 9 Fr in some embodiments) to a second larger size (e.g., 19 Fr in some embodiments) required to accommodate the anchor assembly 50.

[0127] In one specific, non-limiting, exemplary embodiment of the collapsible anchor sheath 404, the sheath has an approximately 0.005-inch wall made of a thermoplastic elastomer material (e.g., Pebax®) configured into three different diameter tubes. For example, two relatively short pieces can be used to transition from a smaller diameter catheter (9 French in one embodiment) to a larger diameter to accommodate the anchor assembly 50 (19 French in one embodiment). The third tube forms the collapsible portion of the sheath itself. All three pieces can be formed on a tapered mandrel using thermal bonding or other suitable molding processes. In a further embodiment, a radiopaque marker, such as a polymeric radiopaque marker band formed from a thermoplastic elastomer containing 60 wt% tungsten, can be incorporated into the sheath and suitably bonded thereto by thermal or other means.

[0128] 22A-F show a ventricular anchor delivery subsystem 400 having a collapsible sheath 404. The ventricular anchor delivery subsystem 400 can be used in the methods and steps described above and can be used with the drive shaft 37, driver head 306, and other components described above to rotate and deliver the anchor assembly 50. The ventricular anchor delivery subsystem 400 includes a sheath 405 having a proximal portion 410, an intermediate portion 412, and a distal portion 414 that includes the collapsible sheath 404. The proximal portion 410 can include a hemostasis valve 416 with a side port 418. In the illustrated embodiment, the intermediate portion 412 and proximal portion 410 of the sheath 405 can be formed from tubing, such as stainless steel hypotubing, which can have an outer diameter of 9 French (Fr). The collapsible sheath 404 can be formed from a separate material that is bonded to or attached to a smaller diameter tube.

[0129] As shown in FIGS. 22D and 22E, the distal end of the collapsible sheath 404 has a larger diameter than the intermediate portion 412. FIG. 22E is a longitudinal cross-sectional view of FIG. 22D. Threads 422 may be formed on the inner surface of the distal end of the collapsible sheath 404 to retain the anchor assembly 50 within the collapsible sheath 404. Thus, in one configuration, the coil 54 of the anchor assembly 50 engages with the threads 422 on the collapsible sheath 404 such that the anchor assembly 50 is retained within the sheath 404. Rotation of the anchor assembly 50 drives the anchor assembly 502 forward through the sheath 404. In this manner, the sheath 404 supports the anchor assembly 50 during delivery to prevent the anchor assembly 50 from becoming dislodged from the delivery sheath 404 during delivery. Additionally, the larger diameter distal end of sheath 404 is collapsible to fit over the inner diameter of delivery catheter 100 so that collapsible anchor delivery sheath 404 can be retracted into delivery catheter 100. In an alternative embodiment, sheath 404 may include grooves, protrusions, or other elements for engaging anchor assembly 50.

[0130] Typically, the sheath 404 may include any of a variety of interference elements that removably engage an implantable device, such as a helical tissue anchor, and resist axial withdrawal from the helical anchor when positioned within the sheath. Rotating the anchor in a first direction relative to the sheath moves the anchor axially distally as the helix disengages from the sheath. The interference element may be a helical (radially outwardly extending) channel or a helical (radially inwardly extending) ridge that extends for at least about one, two, four, or more full revolutions about the inner circumference of the sheath. In certain exemplary embodiments, the interference element may be a helical (radially outwardly extending) channel or a helical (radially inwardly extending) ridge that extends for at least one, two, or four or more full revolutions about or around the inner circumference of the sheath.

[0131] Alternatively, at least about one, two, six, or more radially inwardly extending tabs are provided, each tab rotating less than a full turn around the circumference of the sheath. In certain exemplary embodiments, at least one, two, six, or more radially inwardly extending tabs are provided, each tab rotating less than a full turn around the circumference of the sheath. The engagement tabs may have a circumferential length of less than about 90°, and in some embodiments, a length of less than about 45°, 20°, or 10° or less around the inner surface of the sheath. In certain exemplary embodiments, the engagement tabs may have a circumferential length of less than 90°, and in some embodiments, a length of less than about 45°, 20°, or 10° or less around the inner surface of the sheath. Depending on the desired performance, the implant can be released from the catheter by multiple full turns or by less than a full turn, for example, less than about a half or quarter turn relative to the catheter. In certain exemplary embodiments, depending on the desired performance, the implant can be released from the catheter by multiple full rotations or by less than a full rotation, for example, less than a half or quarter rotation relative to the catheter.

[0132] The catheter sidewall or the rotational anchor driver or both may have torque transfer elements, such as a helical wound or braided sidewall, to facilitate rotation of the driver and prevent rotation of the deployment catheter.

[0133] The sheath extends between a proximal end attached to the catheter shaft and a distal open end, the proximal end having an angled engagement surface for slidably engaging the distal opening of the delivery catheter such that the sheath is transformable from a radially expanded configuration to a radially contracted configuration in response to proximal retraction of the sheath into the delivery catheter.

[0134] The sheath has an axial length corresponding to the intended implant that is generally less than about 15 cm, and in many embodiments, about 10 cm, or 5 cm, or 3 cm, or less. In certain exemplary embodiments, the sheath has an axial length corresponding to the intended implant that is generally less than 15 cm, and in many embodiments, about 10 cm, or 5 cm, or 3 cm, or less.

[0135] In embodiments where the OD of the device is smaller than the ID of the internal passageway of the deployment catheter, the rotational interlock feature described above may be implemented on the interior surface of a flexible (collapsible) sidewall or on a fixed (non-collapsible) sidewall catheter, as described above. In collapsible sheath implementations, when in a radially expanded configuration to accommodate an implantable device, proximal retraction into a delivery catheter having an ID smaller than the sheath OD causes the sheath to collapse after deployment of the device.

[0136] FIG. 22F illustrates a method of forming the collapsible sheath 404. A mandrel 426 having a first diameter 430 and a smaller second diameter 432 is disposed. FIG. 22F is a longitudinal cross-sectional view of the mandrel similar to the end view of FIG. 2E. The smaller diameter portion 432 of the mandrel 426 may be disposed within the distal end of the intermediate section 412. The mandrel 426 may have a transition region 427 between the first and second portions 430 and 432 of the mandrel 426. A coil 450 may be disposed on an outer surface of the larger diameter portion 430 of the mandrel 426. A sheath 452, which forms the collapsible sheath 404, may be disposed over the mandrel 426 and the distal end of the intermediate section 412. In one embodiment, the sheath 452 may include a wall made of an approximately 0.005 inch wall thermoplastic elastomer (such as Pebax). Sheath 452 may be heat treated while on mandrel 426 such that the proximal end of sheath 452 is reduced in diameter and bonded to intermediate section 412, and the distal end of sheath 452 assumes the form of coil 450 to form the internal threads in sheath 404. As previously mentioned, sheath 404 has a radiopaque marker, such as, for example, a polymeric radiopaque marker band formed from a thermoplastic elastomer containing 60 wt% tungsten, incorporated into the sheath and thermally or otherwise suitably bonded to sheath 404. In one embodiment, the marker is located at the distal end of the sheath.

[0137] FIG. 22G is a side view of a steering zone near the distal end of the delivery catheter 100 that can be articulated or bent in a first direction relative to the central axis of the delivery catheter 100. The delivery catheter 100, as described herein, can be used to deliver various subsystems. Thus, the delivery catheter 100 can be configured to be positioned in the left atrium (as shown in FIGS. 3-6A) or the left ventricle (as shown in FIG. 1). To achieve this position, the delivery catheter 100 can include a steering zone or first curve 102 that angles the distal portion 108 of the catheter 100 away from the proximal portion 106 of the catheter 100. In this manner, the steering zone of the delivery catheter 100 can be actively deflected to form a delivery catheter curve that resides in the delivery catheter curve plane (also referred to herein as the first plane or XY plane). As shown in FIG. 22G, the delivery catheter 100 can bend through a range of angles. For example, the delivery catheter 100 can be articulated to include a first curve 102 such that the central longitudinal axis of the portion of the delivery catheter 100 distal to the curve forms an angle A with the central longitudinal axis of the portion of the delivery catheter proximal to the curve 102. The angle A can be between 10 and 150 degrees, and in certain embodiments, the angle A can be between 30 and 80 degrees, and in certain embodiments, between 35 and 70 degrees. In some examples, the first curve 102 can be gradual, with a radius of curvature of at least 0.9 inches. In some examples, the first curve 102 can have a radius of curvature between 0.5 and 1.0 inches. The delivery catheter 100 can include various devices and mechanisms for articulating the steering zone, such as, for example, various combinations of pull wires that can be used to steer the catheter 100.

[0138] 22H is a perspective view of an embodiment of a ventricular anchor delivery sheath 700 that may include an elongated, flexible tubular body having a proximal end, a distal end, and a longitudinal axis. The ventricular anchor delivery sheath 700 may include a proximal preset curve 702 and a distal preset curve 704 and may be axially advanced through a delivery catheter 100. An access system may include the delivery catheter 100 and the ventricular anchor sheath 700 for directing the ventricular anchor sheath to a target site within the left ventricle. The ventricular anchor sheath 700 may have a proximal portion 706, an intermediate portion 708, and a distal portion 710. As shown, the ventricular anchor sheath 700 may include a collapsible sheath 404 at the distal end of the distal portion 710, which may be configured as described above, with the distal end of the collapsible sheath 404 forming the distal end of the ventricular anchor sheath 700. The collapsible sheath 404 can be a distal anchor section having a collapsible sidewall. The proximal preset curve 702 can be positioned between the proximal portion 706 and the intermediate portion 708. The distal preset curve 704 can be positioned between the intermediate portion 708 and the distal portion 710. The ventricular anchor sheath 700 can have the proximal preset curve 702 and the distal preset curve 704 pre-formed or preset such that the ventricular anchor sheath 700 assumes the configuration illustrated in FIG. 22H when not constrained by an outer sheath, such as the delivery sheath 100 described above. The proximal preset curve 702 can be proximal to the distal preset curve 704. The distal preset curve 704 can be distal to the proximal preset curve 702. In certain embodiments, the ventricular anchor sheath 700 is heat set to the shape shown in Figure 22H by placing the vertical anchor sheath 700 over a mandrel having the desired shape and then heat treating the sheath 700 to apply a preformed shape to the sheath 700 to form the proximal and distal preset curves 702, 704. In some examples, the ventricular anchor sheath 700 can be shaped by applying heat and manually bending the ventricular anchor sheath 700 around a fixture to achieve the desired shape.In another example, the ventricular anchor sheath 700 can also be shaped by loading the ventricular anchor sheath 700 into a cassette having a pre-set shape and applying heat to set the ventricular anchor sheath 700 into the desired shape.

[0139] The proximal preset curve 702 of the ventricular anchor sheath 700 can be curved within a proximal preset curve plane (also referred to as the XY plane or first plane) to create a range of angles B between the central longitudinal axis 705 of the proximal section 706 and the central longitudinal axis 715 of the intermediate section 708. For example, angle B can be between 70° and 100°, and in certain embodiments, between 85° and 95°, and in certain embodiments, 90°. In some examples, the proximal preset curve 702 can be gentle, such as having a radius of curvature of 2.0 inches. In some examples, the proximal preset curve 702 can have a radius of curvature between 0.5 and 3.0 inches. As described below, the proximal preset curve 702 can assist or orient the ventricular sheath 700 within the delivery catheter 100. For example, the proximal preset curve 702 can have a radius corresponding to or similar to the radius of the first curve 102 of the delivery catheter 100. Thus, as the ventricular sheath 700 is advanced through the delivery catheter 100, the proximal preset curve 702 causes the distal portion 7100 of the ventricular sheath 700 to assume a particular rotational orientation within the delivery catheter 100 such that it resides in a particular rotational orientation when it resides in the delivery catheter 100. Thus, the distal portion 710 of the ventricular sheath 700 can be oriented in a particular direction when it resides in the delivery catheter 100. If the ventricular sheath 700 is not in the correct rotational orientation, the user can receive tactile feedback in the form of resistance to the axial advancement of the sheath 700 through the delivery catheter 100. Rotating the sheath 700 to the proper rotational orientation reduces this resistance, providing feedback to the user that the sheath 700 is correctly oriented. As shown in FIG. 22H , the proximal preset curve 702 can reside in a first plane 725, which may be referred to herein as the XY plane or the proximal preset curve plane 725.

[0140] As shown in FIG. 22H , the ventricular anchor sheath 700 can be bent to allow portions of the sheath 700 to extend in two different planes. The proximal portion 706, the proximal preset curve 702, and the intermediate portion 708 can reside in a first plane 725, which may be referred to as the XY plane or the proximal preset curve plane, as described above. The Y axis can be perpendicular to the first plane 725, as shown in FIG. 22H . The central longitudinal axis 720 of the distal portion 710 can reside in a second plane 730. The proximal preset curve 702 can be angled within the first plane 725 to move the intermediate portion 708 away from the proximal portion 706, as described above. The distal preset curve 704 can, in turn, be angled within the second plane 730, which may be referred to as the distal preset curve plane or the second plane, moving the distal portion 710 away from the intermediate portion 708. The distal preset curve 704 of the ventricular anchor sheath 700 can form an angle defined between the central longitudinal axis 715 of the intermediate portion 708 and the central longitudinal axis 720 of the distal portion 710. The angle between the central longitudinal axis 715 of the intermediate portion 708 and the central longitudinal axis 720 of the distal portion 710 can have two components: an angle α in the XZ plane, shown in FIG. 22I, and an angle β in the ZY plane, shown in FIG. 22J, such that the distal portion 710 lies in a different plane than the intermediate 708 and proximal portions 710 of the sheath 800 and is angled relative to the XY plane. The intermediate portion 708 can have a length between about 20 mm and 50 mm, e.g., about 32 mm, and the distal portion 710 can have a length between about 20 mm and 50 mm, e.g., about 31 mm. The length of the intermediate portion 708 can be used to control the position of the ventricular implant within the ventricle, such that the ventricular implant can be positioned at the base of the papilla in certain embodiments. The length of the distal portion 710 can be used to control the distance from the centerline of the heart to the heart wall. As described below, the intermediate portion 708 can center the distal portion 710 of the ventricular sheath over the mitral valve. The distal preset curve 704 can direct the distal portion 710 of the sheath 700 from over the mitral valve to a position through the mitral valve toward the ventricle so that a ventricular anchor can be deployed, as described above.

[0141] In exemplary embodiments, the distance between the distal end of the ventricular anchor sheath 700 and the longitudinal center or midpoint of the distal preset curve 704 can be in one embodiment, 30 to 90 millimeters, in another embodiment, 50 to 70 millimeters, and in another embodiment, approximately 60 millimeters. In certain exemplary embodiments, the distance between the distal end of the ventricular anchor sheath 700 and the longitudinal center or midpoint of the distal preset curve 704 can be in one embodiment, 30 to 90 millimeters, in another embodiment, 50 to 70 millimeters, and in another embodiment, 60 millimeters. In exemplary embodiments, the distance between the distal end of the ventricular anchor sheath 700 and the longitudinal center or midpoint of the proximal preset curve 704 can be in one embodiment, 80 to 165 millimeters, in another embodiment, 100 to 145 millimeters, and in another embodiment, approximately 125 millimeters. In certain exemplary embodiments, the distance between the distal end of the ventricular anchor sheath 700 and the longitudinal center or midpoint of the proximal preset curve 702 can be in one embodiment, 80 to 165 millimeters, in another embodiment, 100 to 145 millimeters, and in another embodiment, 125 millimeters. In exemplary embodiments, the distance between the longitudinal center or midpoint of the distal preset curve 704 and the longitudinal center or midpoint of the proximal preset curve 702 can be in one embodiment, 45 to 85 millimeters, in another embodiment, 25 to 105 millimeters, and in another embodiment, approximately 65 millimeters. In certain exemplary embodiments, the distance between the longitudinal center or midpoint of the distal preset curve 704 and the longitudinal center or midpoint of the proximal preset curve 702 can be in one embodiment, 45 to 85 millimeters, in another embodiment, 25 to 105 millimeters, and in another embodiment, 65 millimeters.

[0142] Figure 22I is a top view of the ventricular anchor sheath 700 of Figures 22H-I to illustrate the angle, α, in the XY plane. As shown in Figure 22I, the distal portion 710 can be tilted at an angle α in the range of 5° to 60° relative to the central longitudinal axis of the intermediate portion 708 in the XZ plane. For example, the angle α of the distal preset curve 704 can be approximately 45° relative to the central longitudinal axis of the intermediate portion 708 in the XZ plane.

[0143] FIG. 22J is a side view of the ventricular anchor sheath 700 of FIGS. 22H-I. As shown in FIG. 22J, the central longitudinal axis 720 of the distal portion 710 can be tilted at an angle β relative to the central longitudinal axis 705 of the proximal portion 706 or the Z axis in the XZ plane described above, where the angle β can be within a range of 40 to 75 degrees. For example, the angle β formed by the distal preset curve 704 can be approximately 40 to 75 degrees in the Y direction measured from the Z axis, which can be substantially parallel to the central longitudinal axis 705 of the proximal portion 706. In certain embodiments, the angle β can be 60 degrees. Thus, in the illustrated embodiment, the distal preset curve 704 can reside in a second plane, also referred to herein as the distal preset curve plane, that is rotationally offset from the first plane (i.e., the XZ plane or the proximal preset curve plane) by an angle within a range of 40 to 75 degrees, and in certain embodiments, 60 degrees.

[0144] Figure 22K is a front view of the ventricular anchor sheath 700 of Figures 22H-J. As shown in Figure 22K, the distal portion 710 can be tilted at an angle θ in the x-direction measured from the y-axis. For example, the angle θ of the distal preset curve 704 can be approximately 30-60°, and in some embodiments, 45°, in the x-direction measured from the y-axis, which can be substantially perpendicular to the longitudinal axis 705 of the proximal portion 706.

[0145] In some examples, the distal preset curve 704 may be sharper than the proximal preset curve 702. For example, the distal preset curve 704 may have a radius of curvature of 0.45 inches. In some examples, the distal preset curve 704 may have a radius of curvature between 0.1 and 0.5 inches. In certain examples, the arc length of the distal preset curve is about 50% or less of the arc length of the proximal preset curve, and in certain examples, the arc length of the distal preset curve is about 20% or less of the arc length of the proximal preset curve. In certain exemplary examples, the arc length of the distal preset curve is 50% or less of the arc length of the proximal preset curve, and in certain examples, the arc length of the distal preset curve is 20% or less of the arc length of the proximal preset curve.

[0146] Figure 22L illustrates the placement of a ventricular anchor 302 using the ventricular anchor sheath 700 of Figures 22H-K and the delivery sheath of Figure 22G. The ventricular anchor sheath 700 can be used in the methods and steps described above (e.g., with the drive shaft 307, driver head 306, and other components described above for rotating and delivering the anchor assembly 50). For example, the ventricular anchor delivery sheath 700 can have a catheter 100 inserted therethrough. The ventricular anchor delivery sheath 700 can deliver a ventricular anchor, such as a helical anchor 32.

[0147] The ventricular anchor sheath 700 can be advanced within the delivery catheter 100. When the ventricular anchor sheath 700 is fully inserted within the delivery catheter 100, such that the intermediate section 708 and the distal section 710 are advanced out of the delivery catheter 100, the proximal preset curve 702 of the ventricular anchor sheath 700 can be aligned with the first curve 102 of the delivery catheter 100 and the delivery catheter curve. The proximal section 106 of the delivery catheter 100 can be aligned with the proximal section 706 of the ventricular anchor sheath 700. The intermediate section 708 and the distal section 710 of the ventricular anchor sheath 700 can extend beyond the distal section 106 of the delivery catheter 100, as shown in FIG. 22L. Alignment of the first curve 102 of the delivery catheter 100 with the proximal preset curve 702 of the ventricular anchor sheath 700 can ensure that the distal portion 710 of the ventricular anchor sheath 700 is properly oriented as it exits the delivery catheter 100. For example, the delivery catheter 100 can have the first curve 102 in the delivery catheter curve to position and orient the distal portion 108 within the ventricular atrium. The ventricular anchor sheath 700 can be positioned within the delivery catheter 100 such that the distal portion 710 of the ventricular anchor sheath 700 extends from the distal end of the delivery catheter 100 and is positioned within the left ventricle. The anchor sheath 700 is configured to rotate within the delivery catheter 100 in response to axial alignment of the anchor sheath proximal preset curve within the delivery catheter curve to bias the proximal preset curve surface into alignment with the delivery catheter curve surface. In certain embodiments, the proximal preset curve 702 and the delivery catheter curve 102 are configured to cooperate to provide a tactile indication of the rotational alignment of the anchor sheath 700 within the delivery catheter 100 .

[0148] The ventricular anchor sheath 700 can be positioned such that the proximal preset curve 702 orients the intermediate portion 708 partially into the left atrium and across the valve, and the distal preset curve 704 orients the distal portion 710 into the left ventricle. The delivery catheter 100 can be placed in the left atrium as shown in FIGS. 11 and 12 and 22L. The ventricular anchor sheath 700 can be positioned within the delivery catheter 100 such that the first curve 102 of the delivery catheter 100 aligns with the proximal preset curve 702 of the ventricular anchor sheath 700. A ventricular anchor, such as ventricular anchor 32, can then be inserted through the ventricular anchor sheath 700 for delivery. For example, the ventricular anchor 302 can be delivered into cardiac tissue, for example, near the apex of the left ventricle or near the papillary muscles.

[0149] The proximal preset curve 702 and the distal preset curve 704 of the ventricular anchor sheath 700 can be preset. As described above, in some examples, the ventricular anchor sheath 700 can be manufactured with a curved mandrel to heat set the angle of curvature of the ventricular anchor sheath 700. The ventricular anchor sheath 700 can be substantially flexible and pliable so that the ventricular anchor sheath 700 can be substantially aligned with the delivery catheter 100 when the ventricular anchor sheath 700 is inserted into the delivery catheter 100. For example, if the delivery catheter 100 is substantially straight, the ventricular anchor sheath 700 can be substantially straight when disposed within the delivery catheter 100. When the distal preset curve 704 and distal portion 710 are exposed and unconstrained within the delivery catheter 100, the preset curve of the proximal preset curve 702 aligns with the curved portion 102 of the delivery catheter 100, and the proximal preset curve 704 can direct the distal portion 710 to a desired orientation within the heart. The ventricular anchor sheath 700 can include a distal marker near the second curved portion 704 to indicate how far the inner ventricular anchor sheath 700 should extend beyond the delivery catheter 100. An advantage of the two preset curves (proximal and distal) in the anchor catheter sheath 700 described herein is that when the delivery catheter 100 is positioned centrally above the mitral valve in the atrium, simply advancing the anchor catheter sheath 700 distally from the end of the delivery catheter 100 guides the tip of the anchor catheter sheath 700 to the target location, which may be between the bases of the papillary muscles in the posterior wall of the left ventricle, without any additional catheter manipulation.

[0150] As noted above, the above-described embodiments having preset proximal and distal curves 702 and 704 can advantageously direct the distal end of the anchor sheath to a desired location for the anchor as the anchor sheath exits the delivery catheter. In an alternative embodiment, the anchor sheath 700 can be steerable through the use of pull wires or other mechanisms for steering the catheter. In such an embodiment, the steerable anchor sheath 700 can be configured to have proximal and distal steering zones configured in the positions described above and articulatable through the angles described above relative to the preset proximal and distal curves 702, 704. In another embodiment, a preset mandrel can be provided with the preset proximal and distal curves 702, 704 disposed thereon as described above. The preset mandrel can then be inserted through the ancas sheath such that the ancas sheath assumes the shape of the preset mandrel.

[0151] 23A-C, 24A-D, 25A-B, and 26 illustrate another embodiment of a cutter catheter 500 that may be used to cut sutures 74, 344 in one or more of the procedures and systems described above. For example, once the sutures 74, 344 are locked (secured) within the suture lock 376, the proximal ends of the sutures 74, 344 may be cut adjacent the proximal face of the suture lock 376 using a suture cutter catheter 500 according to one embodiment described herein.

[0152] 23A and 23B, a cutter catheter (also referred to as an endovascular suture cutter) 500 includes an outer sheath 504 extending through a delivery catheter 502 and an inner shaft 506 extending through the outer sheath 504. The proximal end of the outer sheath 504 may be coupled to a luer lock 503. Referring to FIG. 24, the outer sheath 504 is coupled to a cutter housing 510 at its distal end. The cutter housing 510 may be barrel-shaped, forming a cylindrical chamber. The distal end of the cutter housing 510 includes a bore 512. The suture extends through the bore 512 and then through a window 514 formed in the side of the cutter housing 510 to define a suture path extending through the cutter housing 510. In this manner, a suture 74, 344 may be advanced through the cutter housing 510, as shown in FIG. 23C.

[0153] 25A, 25B, and 26, the cutter head 520 is positioned to rotate within the cutter housing 510. The cutter head 520 can have a hollow half-barrel or partial barrel shape that includes a cutting edge 522. The cutting edge 522 has a helical path or curved shape as it extends from the distal end to the proximal end of the cutter head 520. As shown in FIG. 26, the cutting edge 522 can extend along the side of the cutter head 520. Sutures extending through the distal hole 512 and the side window 514 can be cut by rotating the cutter head 520 within the cutter housing 510. The rotation compresses the suture between the cutting edge 522 and the interior surface of the cutter housing 510. Due to the shape of the cutting edge 522, the suture is sliced. This is a more efficient and reliable cutting action compared to a compressing or chopping action.

[0154] Advantageously, as the endovascular suture cutter 500 advances through the heart, the cutting edge 522 of the cutter head 520 is not exposed but is instead covered by the surface of the cutter housing 510. For example, as shown in FIG. 26 , the cutting edge 522 is covered by the inner surface of the cutter housing 510. In the illustrated embodiment, the cutter catheter 500 has a lock 540 at the distal end of the endovascular suture cutter 500 to prevent rotation between the cutter head 520 and the cutter housing 510. In the illustrated embodiment, the lock 540 has a protrusion 550 on the cutter head 520 that engages with a corresponding recess 552 in the cutter housing 510. When engaged, the protrusion 550 and the recess 552 prevent rotation between the cutter head 520 and the cutter housing 510. In this manner, the cutting edge 522 remains in a position where it is not exposed but is covered by the inner surface of the cutter housing 510. The protrusions 520 and recesses 522 may be disengaged by axially advancing the rotation housing 520 relative to the cutter housing 510. In the disengaged position, the cutter head 520 may be rotated relative to the cutter housing 510 to sever the suture as described above. The protrusions 520 and recesses 522 may be reversed in other configurations or located on other portions of the cutter housing 510 and cutter head 520.

[0155] FIG. 27 shows a proximal handle 570 that may be formed around the luer lock 503. The handle 570 may be used to control movement of the cutter head 520 and the cutter housing 510. In this configuration, the cutter head 510 may be fixed relative to the handle 570. The cutter head 520 may be rotationally coupled and connected to the suture cutter handle 572 such that rotation of the suture cutter handle 572 rotates the cutter head 520 relative to the cutter housing 510. As shown, the suture cutter handle 572 is disposed in a retracted position relative to the handle 570, in which the protrusion 550 and recess 552 are engaged to prevent rotation between the cutter head 520 and the cutter housing 510. A lock 578 is provided on the handle 570. By releasing the lock 578, the cutter head handle 572 may be moved axially (e.g., distally in the illustrated embodiment) relative to the handle 570. In this manner, protrusion 550 and recess 552 are disengaged and suture cutter handle 572 rotates relative to handle 570 to cut the suture.

[0156] Pledget with Radiopaque Markers: Figures 28-31 illustrate an embodiment of a leaflet anchor 641 having a pledget 640 and that may be used with the systems and methods described herein. Figures 28 and 29 schematically illustrate one embodiment of a pledget 640 formed by securing the distal end of a suture 644 between two flat sheets 645a, 645b. Figure 29 illustrates a cross-section of the pledget 640 along line BB shown in Figure 28. In some embodiments, the suture 644 is inserted between the two sheets 645a, 645b (e.g., substantially in the center of the sheets) and compressed and / or laminated to bond the three components together (e.g., under heat and / or pressure). At least one layer may be partially sintered. The suture 644 may be flattened and / or densified to improve resistance to suture tearing. The sheet may be a flat polytetrafluoroethylene (PTFE) sheet (e.g., a thin, uncured expanded PTFE (ePTFE) sheet) or any other suitable material. In some implementations, the leaflet sutures 644 may be arranged between the sheets in a zigzag or S-shape. FIG. 30 shows the pledget 640 of FIG. 28 including multiple openings 643 for passing the proximal tails 660 of the sutures 644. In some embodiments, one or more openings 643 may be formed through the pledget in various configurations to form a collapsible structure, as described elsewhere herein, configured to secure the sutures 644 to the leaflets of the mitral valve. FIG. 30 shows openings 643 extending through the center of the pledget, through the sutures 644. In some embodiments, the openings 643 are formed on alternating sides of the sutures 644. In some examples, openings 643 may be formed on the same side of suture 644 (e.g., in wing 641 or wing 642). In the illustrated configuration, multiple openings 643 may be formed through suture 644. Multiple openings 643 may be aligned along the center of pledget 640. Multiple openings 643 may be aligned along the length of suture 644 (e.g., forming a straight line). Openings 643 may extend from a first proximal end to a second distal end of pledget 640.The seam 644 may be at least partially flattened between the two opposing sheets, which facilitates placement of the opening 643 through the seam 644. Various combinations of openings 643 may be used, including the placements described above.

[0157] A radiopaque marker may be added to the pledget 640. For example, in the embodiment shown in FIGS. 28-31 , a marker band 660a may be placed around or around the sutures adjacent the second or distal end of the pledget 640. The marker band 660a may be crimped to the sutures 640 at this location. Then, as shown in FIG. 31 , the proximal ends 660 of the sutures 644 are threaded through the openings 643 formed in the pledget 640, starting from the opening 643 closest to the marker band 660a, thereby positioning the marker band 660a at the distal end of the pledget 640 upon deployment. The pledget 640 may be transformable from an elongated strip-like configuration to a radially expanded and axially shortened configuration by proximal retraction (contraction) of the sutures 644.

[0158] Flexible Pledget Delivery Needle As mentioned above, in certain embodiments, a radially expandable leaflet anchor travels within a hollow needle having a sharp end for penetrating the leaflet. The radially expandable leaflet anchor may comprise a pledget. The pledget may be transformable from an elongated strip-like configuration to a radially expanded, axially shortened configuration by proximal retraction of the suture.

[0159] In some embodiments, the hollow needle includes an outer surface having one or more helical grooves. In other embodiments, the hollow needle may have one or more raised helical coils, such as thin coils, attached to the outside of the hollow needle. FIG. 32 shows an embodiment in which a hollow needle 1204 has a helical coil 1205 attached to its outer surface. Because the leaflet may be moving before, during, and after the puncture process, the leaflet may have a range of motion where a non-grooved hollow needle or a raised helical coil may slip off the leaflet. A grooved surface or a raised helical coil has several advantages. First, if the hollow needle does not fully puncture the leaflet, i.e., if the distal portion of the hollow needle does not allow for pledget delivery, or if the physician determines that the hollow needle may disengage from the leaflet prematurely, the physician can apply force to the catheter or a mechanism within the catheter that transmits rotational force to the needle to further screw the hollow needle into the leaflet tissue and secure the leaflet from disengaging from the needle. Second, once the pledget has been delivered, the physician can remove the needle by applying force to the catheter or a mechanism within the catheter that transfers rotational force to the needle, loosening the hollow needle from the valve leaflet.

[0160] Depending on the catheter system used, the hollow needle can be oriented to puncture the needle from the left atrial side to the left ventricular side of the heart. In other embodiments, the hollow needle can be oriented to puncture the valve leaflet from the left ventricular side to the left atrial side of the heart. Because entry points into the heart from outside the patient can vary, it is desirable for at least a portion of the hollow needle to be flexible. Using a flexible hollow needle allows the hollow needle to navigate all of its curves to access the valve leaflet, allowing the physician to fine-tune the needle's placement before puncturing the valve leaflet. Figure 32 shows a cut 1203 in the hollow needle that provides flexibility to the hollow needle as needed. In some embodiments, the cut 1203 in the hollow needle is formed by laser cutting, machining, or other known methods.

[0161] The system may also include a hollow needle that punctures the valve leaflets via the release of a stored energy source. For example, the stored energy may be a spring, a pressurized liquid, a pressurized gas, an electrically actuated piston, or by other known methods. In some embodiments, the stored energy device is a spring. In a further embodiment, the spring is located in the pledget delivery handle 1202, as shown in FIG. 33.

[0162] The amount of stored energy must provide sufficient force to the hollow needle to puncture the valve leaflet a sufficient distance or depth. As used herein, "sufficient distance or depth" means one or more of: the distal end of the hollow needle completely piercing the valve leaflet without the hollow needle contacting or piercing other structures within the heart; allowing the needle to remain engaged with the valve leaflet while the leaflet moves; and allowing the physician to deliver the pledget. If the needle does not pierce the valve leaflet a sufficient distance or depth, the physician rotates the hollow needle to further advance it through the valve leaflet tissue. If the needle does not puncture the valve leaflet in the correct position, the physician rotates the hollow needle in the opposite direction to remove it from the valve leaflet tissue. The system is then re-armed, i.e., the stored energy is applied to the system to properly position the hollow needle for pledget delivery, and the system is repositioned and activated. In some embodiments, the system includes a controller. The physician places the catheter (including the retracted hollow needle) on or near the valve leaflet, confirms the correct position of the catheter relative to the leaflet, and releases stored energy to puncture the leaflet. At least a portion of the distal end of the catheter, the distal end of the hollow needle, or both, is radiopaque or includes other visualization aids that allow the physician to confirm the correct location of the puncture through the release of the stored energy before delivering the pledget.

[0163] Component Stabilization and Suture Management System: An aspect of the present disclosure, which may be used alone or in combination with the above-disclosed aspects, is a stabilization system for transvascular cardiac repair used to stabilize and / or adjust the position of a proximal portion (e.g., handle) of one or more of the subassembly components described above (e.g., delivery catheter 100 and / or one or more various subsystems that may be advanced to the delivery catheter). The stabilization system may also include a suture management system for adjusting the length and / or tension of one or both of the ventricular anchor sutures and at least one leaflet suture.

[0164] In certain embodiments, the suture management system for transvascular cardiac repair assists the physician in maintaining a substantially fixed force or tension on the suture while adjusting the suture length and setting the tension of the suture lock. Those skilled in the art will appreciate that the term "substantially fixed force" includes allowing small changes in tension to occur. For example, in one embodiment, a 10% change in tension occurs.

[0165] An advantage of using such a suture management system is that it allows the leaflets to continue to move in a "natural" manner in response to the heartbeat during the repair procedure, while maintaining substantially constant tension on the sutures, thereby maintaining each pledget in substantial contact with the leaflet. Furthermore, use of the device can prevent or minimize suture entanglement. A further advantage is that the physician can individually adjust each suture to increase or decrease tension, thereby adjusting the final movement of the leaflets as needed. The suture management system can be located in the operating room near the physician during surgery. After the anchors and leaflet sutures are deployed in the patient, the ends of the sutures that pass through the delivery catheter can be attached to the suture management system and held at the aforementioned substantially constant tension.

[0166] In certain aspects of the present disclosure, aspects of the stabilization system may be beneficial and used independently of aspects of the suture management system or device. Likewise, certain aspects of the suture management system may be beneficial and used independently of aspects of the stabilization system. Nevertheless, as described herein, certain advantages may be achieved by systems utilizing combinations and subcombinations of various aspects of the stabilization and suture management systems described herein.

[0167] 34A and 34B illustrate an example of a stabilization system (referred to as system) 1500. The system 1500 includes a base or tray 1502 that can be placed on a stand or table (not shown) to prevent device movement during a procedure. As shown in FIG. 35 , the base includes an upper or top plate 1504 and a bottom or bottom plate 1506. The upper and lower plates (also referred to herein as upper and bottom plates) 1504, 1506 can be movably connected to one another via an adjustable positioning mechanism 1510 (also referred to herein as an “adjustment mechanism”), which in the illustrated embodiment includes a lower threaded boss 1512 coupled to the lower plate 1506 and an upper threaded boss 1514 coupled to the upper plate 1504. A screw 1516 extends through the lower threaded boss 1512 and the upper threaded boss 1514. Axial movement of the screw 1516 (see FIG. 35 ) relative to the lower plate 1506 is limited such that rotation of the screw handle 1518 moves the upper plate 1504 relative to the lower plate 1506. In this manner, the adjustment mechanism 1510 can be repositioned in the direction of arrow 1520 on the upper plate 1504 (and its coupled components) relative to the lower plate 1506, which is mounted to a stand or table, as needed. The adjustment mechanism 1510 may include a lock to prevent movement between the upper plate 1504 and the lower plate 1506. In some embodiments, other mechanisms may be used to move the upper and lower plates axially relative to one another, such as sliding plates, complementary rails, and second channels or rollers.

[0168] The stabilization portion 1550 of the system 1500 includes multiple components that are used to hold or stabilize the components of the mitral valve chordae tendineae repair device described above. In particular, as described in detail below, the device may be used to hold or stabilize the proximal portion (e.g., handle) of the introducer sheath, the delivery catheter 100, the ventricular anchor delivery subsystem 300, the suture locking delivery system 370, the pledget delivery subsystem or handle 1202, and / or the handle or proximal end of the suture cutter catheter 500. Such components may be configured according to the embodiments and aspects described herein.

[0169] For example, the system includes a first docking platform 1600 that may be disposed at a distal portion of the system 1500. The first docking platform 1600 is referred to herein as the “distal docking platform 1600.” The distal docking platform 1600 may be configured to hold or stabilize a handle or proximal portion of an introducer catheter. Various components of the delivery subsystem described herein are advanced through the introducer catheter. Referring to FIG. 35 , the distal docking platform 1600 includes a first stabilizing device 1602 in the form of a clamp 1602. The first stabilizing device 1602 may be configured to clamp around an annular portion of a catheter, such as an introducer or access sheath. In the illustrated embodiment, the clamp 1602 includes a pair of clamp plates 1604, 1606 that move toward or away from each other via a threaded post 1608 coupled to a handle 1610. Thus, in the illustrated arrangement, manipulation of a control device, such as rotation of handle 1610, causes plates 1604, 1606 to clamp (secure) an introducer sheath (not shown) to system 1500. In some embodiments, other mechanisms may be used in first stabilizing device 1600 to stabilize the catheter or introducer sheath, such as a friction fit device, a collet, or a device that securely connects to an engaging feature on the handle of the introducer sheath.

[0170] 34A, 34B, and 35, the clamp may be coupled to the top plate 1504 and base 1502 by an arm 1620. The arm 1620 has an "L" shape that positions the clamp 1602 axially above and forward of the top plate 1504. The arm 1620 may be coupled to the top plate such that movement of the top plate 1504 relative to the bottom plate 1506 causes the clamp 1602 to move axially.

[0171] 36, the distal docking platform 1600 includes a second stabilizing device 1650. In the illustrated embodiment, the second stabilizing device 1650 is in the form of a clamp and is provided on the arm 1620. In the illustrated embodiment, the second stabilizing device 1650 may be located at the elbow of the arm 1620. The second stabilizing device 1650 may be used to stabilize other components of the mitral valve repair systems described herein. For example, the second stabilizing device 1650 may be used to stabilize the proximal end (or handle) of a suture lock delivery subsystem (see, e.g., FIG. 14).

[0172] The illustrated second stabilizing device 1650 includes a clamp 1652 for holding components. See FIG. 34A. In the illustrated embodiment, the clamp 1652, like the first stabilizing device, comprises a pair of plates that move toward or away from each other via a control mechanism, such as a screw. Thus, in the illustrated configuration, rotation of the screw causes the plates to clamp (secure) a portion of the suture locking delivery subsystem (not shown) to the system 1500. In some embodiments, other mechanisms, such as a frictional engagement device or a device that positively connects to an engagement feature of the suture locking delivery subsystem, may be used on the forward mount to stabilize the suture locking delivery subsystem. As shown in FIG. 36, the arm may include a platform 1660 that may be used to support a portion of the handle or other portion of the suture locking delivery subsystem. In one configuration, the second stabilizing device 1650 may be used to secure a forward portion of the suture locking delivery subsystem while a rearward portion or rear of the handle / suture locking delivery subsystem rests on the platform 1660.

[0173] 35 and 36 , the system 1500 includes a second docking platform 1700. The second docking platform 1700 is positioned proximal to the first docking platform 1600 and is referred to herein as the proximal docking platform 1700. The proximal or second docking platform 1700 is supported above the base 1502 by an arm 1702 extending from the top plate 1504. The proximal docking platform 1700 may be located at the same height as the previously described stabilizing device. The proximal docking platform 1700 can include components of a suture management system, which will be described in more detail below. The proximal docking platform 1700 includes a third stabilizing device 1710. The device 1710 can include an elongated concave support surface, such as an axially extending U-shaped channel, that can be used to support components such as a handle of a ventricular anchor delivery subsystem according to embodiments described herein. The second docking platform 1700 can be coupled to the top plate 1504 via arms 1702 such that movement of the top plate 1504 moves the platform 1700. Thus, in the illustrated arrangement, the proximal docking platform 1700 and the distal platform 1600 are supported by the top plate, and in some embodiments, are fixedly supported by the top plate.

[0174] 35 and 36 , the system 1500 includes a third docking platform 1800. The third docking platform 1800 may be disposed between the first and second docking platforms 1600, 1700 in the axial direction of the attached instrument. As previously mentioned, the first and second docking platforms 1600, 1700 are disposed distally and proximally relative to one another, respectively. The third docking platform 1800 is also referred to herein as the intermediate docking platform 1800. The intermediate docking platform 1800 includes a fourth stabilizing device 1802, which may be in the form of a vise or clamp. The intermediate docking platform 1800 is disposed between the first and second docking platforms 1600, 1700. The intermediate docking platform 1800 includes an adjustment mechanism 1810. In the illustrated embodiment, the adjustment mechanism 1810 may include a threaded engagement between the stabilizing device 1802 and a lower rail 1812. The lower rail 1812 may be fixed relative to the upper plate 1505. Rotating the screw 1816 moves the stabilizer 1802 relative to the rail 1812 and upper plate 1504. The adjustment mechanism 1810 is relocated to the lower plate 1506, which is attached to a stand or table as needed, in a fourth stabilizer (and components coupled thereto). The adjustment mechanism 1810 may have a lock to prevent movement. The intermediate docking platform is supported on the upper plate 1504. The adjustment mechanism 1810 is also relocated to components supported by or fixedly supported on the upper plate, such as the upper plate 1504 and the distal and proximal docking platforms (and components coupled thereto), in the fourth stabilizer (and components coupled thereto).

[0175] In one embodiment, the fourth stabilizing device is used to stabilize a delivery catheter, such as the delivery catheter 100 described above. In certain embodiments, the first stabilizing device 1650 is used to stabilize an introducer catheter, and the fourth stabilizing device 1802 is used to stabilize the delivery catheter 100 that is inserted into the introducer catheter. In this manner, rotation of the screw 1816 allows for small movements of the delivery catheter relative to the introducer catheter. That is, movement of the intermediate docking platform allows movement of the delivery catheter relative to the distal docking platform and its attached introducer catheter.

[0176] 37 and 38, the suture management system 1700 includes at least one, two, three, or more tensioning elements that are used to hold each suture and help keep the suture under tension at all times, thus avoiding slack that could cause the pledget to be pulled into the left atrium or ventricle from the forces generated by each heartbeat, and further preventing slack sutures from tangling in the left atrium or ventricle or preventing slack sutures from tangling with other chordae tendineae in the left ventricle.

[0177] For example, in one embodiment, the anchor sutures are attached to anchor tension element 1720. Anchor tension element 1720 has a rotating spool 1712. Rotating spool 1712 includes a torque-limiting fastener, such as a clutch, for limiting the amount of tension applied to the sutures wrapped around the spool (e.g., the sutures coupled to the ventricular anchor). If excessive tension is applied to the anchor sutures, anchor tension element 1720 can advantageously avoid or reduce the risk of the anchor being pulled out of the heart wall. In other embodiments, anchor tension element 1720 may include a spring-loaded strut structure that applies tension to the sutures. In one embodiment, the proximal ends of the sutures coupled to ventricular anchor 302 of ventricular anchor delivery subsystem 300 are wrapped around anchor tension element 1720 after the ventricular anchor is deployed. In this manner, a constant tension is applied to the suture, and a torque limiting fastener, such as a clutch, prevents or limits excessive tension from being applied to the ventricular anchor. In one embodiment, the clutch has a torque limit of about 2N to about 5N. In certain embodiments, the clutch has a torque limit of 2N to 5N.

[0178] 37 and 38, at least one, two, three, or more suture adjustment fingers 1770 are provided to allow adjustment of the tension of the sutures of the pledget against the valve leaflets. During use, the sutures coupled to the pledget are attached to a tensioning device, such as a weight 1750, to provide the desired tension. In certain embodiments, the weight is about 2 to about 8 grams. In certain embodiments, the weight is between 2 and 8 grams. In the illustrated embodiment, the weight 1750 is accommodated in the proximal platform 1700 by providing a weight attachment, such as a plurality of holes (openings), recesses, or sockets, that receive the weight 1750. The sutures (e.g., leaflet sutures) are positioned in suture guides 1760, which are notches or grooves formed in the platform 1700. The guides 1760 may be configured to allow the sutures to slide axially while providing some constraint on lateral movement. The proximal docking platform 1700 has at least one, two, three, or more suture guides 1760. The ends of the sutures (e.g., leaflet sutures) attached to the weights 1750 can be hooked onto the edges of the platform 1700 to apply a constant tension to the sutures of the pledget, which acts to limit or prevent tangling of the sutures. As previously mentioned, the platform 1700 includes a plurality of guides 1760 that hook onto the edges of the platform 1700.

[0179] 37 and 38, the platform 1700 includes suture adjustment mechanisms or fingers 1770 located near or adjacent to the notches or grooves 1760. The suture adjustment mechanisms 1770 include or consist of rotating spools. Each spool has a slot 1774 through which the suture extends. The rotating spools 1770 can be rotated to adjust the tension on the suture.

[0180] The suture management system provides a dynamic leaflet management system. An advantage of using such a system is that, during the repair procedure, each pledget is maintained in substantial contact with the valve leaflet by applying a substantially constant tension to the sutures, while allowing the leaflets to continue to move in a "natural" state in response to the heartbeat. Furthermore, use of the system prevents or minimizes suture entanglement. A further advantage is that the physician is provided with the ability to individually adjust each suture to decrease or increase tension as needed to tailor the final movement of the valve leaflets. For example, in one embodiment, after advancing the suture lock (as in the previously described embodiment) into the patient and before locking and cutting the sutures, the tension of the sutures can be adjusted while observing the valve's movement. This can be accomplished by rotating a spool to increase or decrease the slack in the wire and the corresponding tension. Once the desired tension is achieved, the suture lock can be activated as described above.

[0181] Multiple sutures, for example up to four, may be secured to the suture management device, and multiple suture management devices may be used as needed. The components of the device may be comprised of any suitable sterilizable material that meets the performance requirements of the device, including, by way of non-limiting example, stainless steel, acetal resins such as polyoxymethylene, PTFE, aluminum, 3D printed resin materials, etc.

[0182] Leaflet Tissue Anchor Deployment System According to a further aspect of the present disclosure, an alternative leaflet tissue anchor deployment system is provided. Referring to FIG. 39 , a needle deployment catheter 332 axially reciprocates a needle 336. A radiopaque marker band 1900 is provided at the distal end of the needle deployment catheter 332 so that the position of the marker band 1900 can be visualized in relation to the mitral valve leaflets while the needle 336 is retracted proximally into the catheter 332.

[0183] In FIG. 39 , the needle 336 is shown in a distally advanced configuration. The needle 336 comprises a tubular body 1902 having a sidewall 1904 and at least one flexibility-enhancing feature, such as a slot pattern. In the illustrated embodiment, at least one serpentine slot 1906 extends through the sidewall. The serpentine slot 1906 may be formed by various methods known in the art, such as laser etching a hypotube. The serpentine slot 1906 improves the lateral flexibility of the needle 336 along the flexure zone, facilitating proper targeting of the needle 336 at the mitral valve leaflets. The flexure zone is typically less than about 4 cm or less than about 2 cm in length, but is long enough to accommodate the full length of the pledget. In certain embodiments, the flexure zone is typically less than about 4 cm or less than 2 cm in length, but is long enough to accommodate the full length of the pledget.

[0184] Needle 336 terminates distally in a sharpened tip 1908 that is spaced from tubular sidewall 1904 by a beveled surface 1910. The bevel angle of beveled surface 1910 is typically within the range of about 30° to 85°, alternatively within the range of about 70° to 80°, and in one embodiment, is about 75°. In one embodiment, the bevel angle of beveled surface 1910 is typically within the range of about 30° to 85°, alternatively within the range of about 70° to 80°, and in one embodiment, is 75°.

[0185] The at least one tissue retaining element 1912 is configured to allow rapid, forceful distal advancement of the needle 336 through tissue, but resist proximal retraction of the needle 336 from the target tissue. The retaining element 1912 may have a variety of structures extending radially outward from the tubular sidewall 1904, such as at least one, two, five, ten, or more barbs, annular rings, or tabs. In the illustrated embodiment, the retaining element 1912 has an annular ring in the form of a continuous helix 1914, which may be formed from a polymer strand or metal wire helically wound around the tubular body 1902. In one embodiment, the helical wire is, for example, 0.008 inch wire, and is welded or otherwise secured to the tubular body 1902.

[0186] Advancement of the needle 336 distally from the diploma catheter 332 at sufficient speed allows the needle 336 to penetrate the valve leaflet without the need for a leaflet stabilization anchor, shown at 406 in FIG. 3. The retention element 1912 sufficiently holds the leaflet on the needle until the pledget is deployed. The needle is then retracted proximally without being rotated, or rotated to loosen the needle and remove it from the leaflet.

[0187] If additional leaflet stabilization is desired, it can be achieved through the temporary leaflet anchors described above, alternative mechanical techniques to grasp or grip the leaflets, or aspiration or cryograsping with a cryo-catheter. These techniques include cryo-catheters of the type used in ablation procedures to freeze target tissue. Cryo-ablation catheters used for atrial fibrillation often accidentally attach to the mitral valve leaflets and must be stopped to release the attached leaflets. This same cryo-attachment can be used to locate and separate the problematic leaflet for stabilization during deployment of the leaflet anchor deployment needle. Cryo-catheters use gas exchange (NO or argon) to reduce the temperature at the tip of the catheter, which can reach temperatures as low as minus 75 degrees Celsius.

[0188] Actuator Control System Deployment of the mitral valve leaflet anchors described herein is accomplished by piercing (piercing) the leaflets from the atrial side of the valve. By avoiding the need for a grasping structure to capture and support the leaflets during piercing, and by using a needle such as that shown in FIG. 39, distal exit of the leaflet anchor deployment needle can be timed to correspond to peak ventricular (systolic) pressure occurring near or around the QRS complex. This synchronizes leaflet piercing with mitral valve closure, allowing systolic pressure within the ventricle to provide the necessary backup support during penetration of the leaflet from the atrium.

[0189] The timing of leaflet needle firing with the cardiac cycle may be performed manually by a clinician or may be partially or fully automated depending on the desired implementation. For example, a visual or audio signal or fluoroscopic image may alert the clinician to the timing of the QRS complex, and the clinician may press a firing trigger or other control to deploy the needle. Because clinician reaction times can vary, it may be desirable to partially or fully automate the needle firing procedure.

[0190] For example, needle 338 may include an automatic needle driver, such as a solenoid carried by the proximal end of the catheter, that is activated to eject the needle distally in response to an activation signal that corresponds in time to a target time in the cardiac cycle, such as during closure of the mitral valve.

[0191] Alternatively, the activation signal may be a visual, tactile, or audible signal to the clinician in response to which the clinician operates a control such as a button or slider to manually advance the needle, or operates a control device that activates an electromechanical or mechanical needle driver.

[0192] In another embodiment of the present disclosure, needle deployment may be performed manually by the clinician, but only after disabling a lockout. In this embodiment, a removable mechanical interference may be formed on or coupled to a proximal portion of the needle shaft. The distally facing interference surface may be a radially outwardly extending tab or annular flange coupled to the needle, or may be provided on the distal surface of an opening extending through the needle. For this purpose, "needle" refers to the needle itself, as well as any proximally extending structure (e.g., an extension tube or rod) that is mechanically coupled to the needle and moves with the needle, as understood by those skilled in the art.

[0193] The proximally facing interference surface is configured to be movable between an engaged state in which it engages the distally facing interference surface of the needle by an interference fit (frictional engagement) and a disengaged state in which the distally facing interference surface and corresponding structure are free to advance distally to withdraw the needle. The proximally facing interference surface is provided on a stopper, such as an axially movable pin or a pivotable or sliding lever movably carried by the proximal handpiece. A stopper driver, such as a solenoid, is configured to move the stopper between the engaged and disengaged states.

[0194] A stopper may be initially engaged to prevent needle deployment. In response to an activation signal indicating a target time (e.g., during, around, or around the QRS complex), the stopper retracts to a disengaged state. This prevents the clinician from prematurely deploying the needle but allows the clinician to manually deploy the needle at the desired target time. To prevent late needle deployment and create a narrow window allowing the clinician to fire the needle, the stopper automatically returns to the engaged state after a preset time window following the activation signal. If the clinician fails to deploy the needle in time within the window, they will have another opportunity to fire the needle, followed by the QRS complex.

[0195] Various techniques have been developed to directly detect the QRS complex or to detect proxies for points in the cardiac cycle. Direct detection techniques include power spectral analysis, bandpass filtering, differentiation, template matching, and real-time techniques relying on waveform functions. Proxies include blood pressure measured in the arterial or venous chambers, atria or ventricles, or noninvasively measured blood pressure, such as peripheral blood pressure. Because the aortic valve is open when the mitral valve is closed, venous measurements serve as a proxy for the timing of the QRS complex, resulting in a distinct feature in the periodic venous pressure curve. Data from any of the aforementioned sources is preferably adjusted to take into account the time delay from the true QRS complex, depending on the desired time sensitivity. ECG signals can also be obtained from conventional ECG monitors, typically already present and operational in the operating room.

[0196] A typical ECG waveform consists of a P wave, indicative of atrial depolarization, a QRS complex, indicative of ventricular depolarization, a T wave, indicative of ventricular repolarization, and possibly a U wave, which may indicate prolonged repolarization. The primary activity of an ECG typically involves identifying the QRS complex in real time for various monitoring and diagnostic purposes. The QRS complex or QRS wave typically lasts approximately 80-120 milliseconds and corresponds to the onset of ventricular contraction and ejection of blood through the aortic valve. In certain embodiments, the QRS complex or QRS wave typically lasts approximately 80-120 milliseconds and corresponds to the onset of ventricular contraction and ejection of blood through the aortic valve. This corresponds to the pressure-responsive closure of the mitral valve, which is important for purposes of this disclosure.

[0197] 40-45 illustrate a system that provides control of an actuator in synchronization with the heart 10. As used herein, an actuator refers to something that is activated in response to a control signal triggered by an event in the cardiac cycle, such as visual, audio, or tactile feedback to the clinician, an automated needle firing mechanism, or a lockout mechanism in a manually operated needle deployment embodiment that prevents the clinician from deploying the needle until the actuator unlocks the firing mechanism.

[0198] Such a system is shown generally in Figure 40. The illustrated system includes components for sensing a cardiac cycle 212, components for generating a trigger pulse for an actuator in response to the sensed cardiac cycle 218, components for positioning the leading edge of the trigger pulse at a specified time within the cardiac cycle 232, components for defining the width of the trigger pulse occurring during the cardiac cycle 234, and components for controlling the firing of the actuator in response to the trigger pulse and for a period of time in response to the defined width 222.

[0199] In particular, an electrocardiogram (ECG) unit 212 is electrically connected to the patient's heart 10 to sense the cardiac cycle and provide an ECG signal 216. The ECG unit 212 may be connected to the heart in any known manner for sensing cardiac signals, including surface-mounted electrodes typically attached to the patient's chest and internal or intracavitary electrodes. Alternatively, the sensing connection may be integrally incorporated with the catheter 332, such as through the provision of one or more electrical leads extending through the catheter 332 to conduct electrical signals or the manipulation of a sensor (e.g., a pressure sensor) or electrode at the distal end of the catheter 332. The electrodes may be unipolar, using surface contact, or bipolar. The electrical leads may extend proximally through the catheter 332 and then terminate in a standard electrical connector that is removably connected to the ECG unit 212 and transmits the sensing signal 216.

[0200] The signal 216 is sent to a trigger generator 218. The trigger generator 218 provides a trigger pulse 220 to an actuator firing circuit 222. The actuator firing circuit 222 energizes an actuator 224, such as to fire the needle or remove a barrier that inhibits the clinician from firing the needle prematurely.

[0201] The position of the trigger pulse 220 in the cardiac cycle of the ECG signal 216 is determined by a pulse positioning circuit 232. The width of the pulse 220 and its duration within the cardiac cycle are determined by a pulse width circuit 234. The trigger generator 218 and pulse positioning circuit 232 and pulse width circuit 234 are included as add-on boards in a PC or microprocessor 236, in which case the system can be controlled via the computer keyboard and appropriate software. The PC 236 and ECG 212 may have separate monitors or may have a single monitor 238 that displays both the ECG and information related to or surrounding the trigger pulse 220.

[0202] The trigger generator 218 may include a marker pulse circuit 250 that provides a marker pulse 252 and a trigger pulse circuit 254 that generates the trigger pulse 220 in response to the marker pulse 252. Alternatively, the marker pulse circuit 250 is included in the ECG itself.

[0203] This can be understood in more detail with reference to FIG. 44. Here, the ECG signal 216 can be viewed as consisting of a series of cardiac cycles 256a, 256b, 256c, including waveforms Q, R, S, and T. When waveform R crosses a preselected threshold 258, a marker pulse 252a, 252b, 252c is generated. Trigger pulses 220a, 220b, 220c are then generated by the trigger pulse circuit 254. The position and overall width 262 of the leading edge 260 of each trigger pulse 220 are determined by the pulse positioning circuit 232 and the pulse width circuit 234. In response to the trigger pulses 220, firing pulses 264, shown as 264a, 264b, 264c in FIG. 44, are generated to energize the actuator 224.

[0204] FIG. 42 illustrates the actuator firing circuit 222. The actuator firing circuit 222 includes a gate 270 that inhibits the delivery of the trigger circuit 220 to the actuator laser power supply 272 (if relevant) in the actuator unit 224. The inhibiting effect of gate 270 is realized when the operator activates switch 274. However, the trigger pulse 220 is inhibited by arming circuit 276, which has an inhibiting effect realized by operation of arming switch 278. This double lock on the delivery of the trigger pulse 220 to the actuator power supply 272 ensures that actuator firing is truly desired and not accidental. Therefore, the operator must first arm the system by operating arming switch 278 to enable arming circuit 276. Then, and only then, does the operator pass the next-occurring trigger pulse 220 to the actuator power supply 272 via gate 270 by activating switch 274. Suitable design details for synchronizing a trigger signal with the QRS complex are disclosed in U.S. Patent No. 5,674,217 to Wahlstrom et al., filed November 16, 1993, the disclosure of which is incorporated herein by reference in its entirety.

[0205] Meltable Sutures: In certain embodiments, the disclosed systems may use polytetrafluoroethylene (PTFE) or expanded polytetrafluoroethylene (ePTFE) sutures due to their desirable tensile strength and relatively low creep. However, sutures made from PTFE and ePTFE cannot be easily severed by cutting or melting.

[0206] To overcome this challenge, some embodiments of the present disclosure relate to sutures in which at least a portion of the suture is meltable. In some embodiments, the suture may be a bicomponent suture, in which the distal end of the suture comprises a meltable suture material and the proximal end of the suture comprises a non-meltable suture material. In some embodiments, the distal portion of the suture comprises less than 50% of the total length of the suture. In other embodiments, the proximal end of the suture comprises more than the total length of the suture. In other embodiments, the bicomponent suture comprises a portion of the suture that is meltable, and the meltable portion is a relatively small meltable region comprising non-meltable suture material on either side of the meltable region. The meltable region should be positioned at the suture location so as not to affect the tensile strength or creep resistance of the implanted prosthetic chordae. When using a bicomponent suture, the junction between the meltable and non-meltable portions should be positioned near the point where the suture will be tied or the location of the suture lock so as not to affect the strength of the suture. After implantation of the artificial chordae, the dissolvable sutures should be under no tension, or only a relatively small portion of the suture should be under tension, during normal heart function. The two-component suture should have sufficient tensile strength along its entire length, especially at any interface (junction) between the fusible and non-fusible portions, to allow the physician to apply sufficient tension to the suture during the tensioning step so that the suture will not collapse (break) when tensioned to correct mitral regurgitation.

[0207] 46 is a schematic side view of a heart showing the left atrium 3301 and left ventricle 3302 separated by the posterior and anterior mitral valves (not numbered), according to one embodiment. In this example, a pledget 3303 is secured to the ventricular valve leaflet, and a portion of a non-dissolvable suture 3304 extends from the pledget into the left atrium 3301, between the two leaflets, and into the left ventricle 3302. In the left ventricle 3302, a tissue anchor 3305 is secured to the cardiac tissue by a helical anchor 3306. A non-dissolvable suture 3308 is joined to the non-dissolvable suture 3304 via a knot 3307. Only a portion of the dissolvable suture 3309 is shown after it has been cut, with the remaining distal end of the dissolvable suture retracted through the catheter (not shown). In this example, all tension from the beating heart is on the sutures 3304, 3308, with substantially no tension on the dissolvable suture 3309. The length of the distal end of the suture should be as short as possible. Note that only the distal portion of one of the sutures 3304, 3308 is shown.

[0208] The system further includes a suture cutter. Once tension is set on the one or more sutures and mitral regurgitation is corrected or minimized, the suture cutter can be advanced through a catheter disposed over the distal ends of the one or more sutures to melt the dissolvable sutures and cut the sutures. The distal ends of the dissolvable sutures are retracted through the catheter for removal from the patient. Each of the one or more sutures can be cut one at a time, or two or more sutures can be melted at a time. The suture cutter includes a heat source, e.g., a coil, to which an electric voltage is applied to heat the coil such that the temperature adjacent the coil rises above the melting temperature of the dissolvable sutures.

[0209] 47 shows an embodiment in which a suture cutter 3310 is advanced through a catheter (not shown) over the distal end of the suture 3311 to the suture lock 3312. The sutures connected to the leaflet pledgets 3303 and the sutures connected to the anchors 3306 that are tensioned to minimize or correct mitral regurgitation are secured (clamped) to the suture lock 3312 so that the sutures cannot move through the suture lock 3312 when tension is applied to the sutures during normal heart function. The suture cutter 3310 includes a heat source, e.g., a heater coil 3315; a short length of tubing coaxial with the heater coil 3315, including a heater housing 3316, and having an inner diameter larger than the outer diameter of the heater coil to insulate the cardiac structures from heat; a hypotube 3317 to prevent blood from entering the catheter; and an insulated conductor 3318 that supplies electrical energy to the heater coil to provide a temperature above the melting point of the fusible suture. The supply of electrical energy to the heater coil is initiated by the physician when the suture cutter is moved into position and is terminated by the physician after the suture is severed. In FIG. 47, the non-fusible suture (unnumbered) extends beyond the suture lock (toward the suture cutter), and the fusible portion of the suture is positioned coaxially with and inside the inner diameter of the suture cutter coil. In this manner, when the distal portion of one or more sutures is removed, only a relatively short portion of the suture ends or tails extend beyond the suture lock, and the remaining portions of the sutures extending to the valve leaflets and ventricular anchors are non-fusible sutures that remain firmly secured to the suture lock.

[0210] Meltable suture components include suitable meltable compositions, including, but not limited to, polyolefins, polyethylene, ultra-high molecular weight polyethylene, polypropylene, polyesters, polyamides, polyglycolide / L-lactide, polyethylene terephthalate, silicones, amino acid proteins such as collagen, and combinations thereof. In some embodiments, a portion of the suture is meltable using any one of the polymers previously described as the meltable portion of the suture or meltable region. The non-meltable portion of the suture may be PTFE or ePTFE.

[0211] Suture Lock Guide: The above-described embodiments provide an effective mechanism for transcatheter mitral valve chordae tendineae repair, e.g., implantation and efficacy of prosthetic chordae. The following embodiments build upon many of the concepts described above to provide additional advantages. For example, normal function of the heart can cause cyclical motion and stresses to the mitral valve chordae tendineae repair system. In particular, the normal compression cycle of the heart can cause the suture lock or other components (e.g., sutures) to vibrate or move within the ventricle. This motion is illustrated in FIG. 48. Arrows 4180 and 4182 indicate the motion of the suture and the suture lock, respectively.

[0212] The oscillatory motion of the sutures and suture locks can contribute to excessive wear at the sutures, particularly at the junctions between the suture lock and the suture. The resulting wear can ultimately lead to premature deterioration and failure (rupture) of the prosthetic chordae. In particular, in some systems, the sutures pass, for example, longitudinally through the suture lock. The sutures connecting the mitral valve leaflets to the anchors extend from one end of the suture. The weight of the suture lock pulls the other end of the suture lock slightly downward in an orthogonal direction, and this angular movement presses the sutures against the suture lock. If the suture lock forms an acute angle, this angle can result in shear forces that can cause the sutures to prematurely rupture (fail). For example, FIG. 49 shows a suture lock 4206 whose orientation positions the suture 4211 against an acute angle in the suture lock 4206. During movement of the suture 4211 and suture lock 4206, the acute angle creates a shear force on the suture 4211. The suture 4244 may experience similar shear forces. These shear forces may be amplified by the rotational movement of the suture lock 4206, as shown by arrow 4202.

[0213] Furthermore, as tension on the suture increases, the suture lock tends to rotate in a direction generally perpendicular to the suture, as shown, for example, in FIG. 50. This movement, in addition to the mass and resulting inertia of the suture lock during other movements, imposes high impact forces on the suture, e.g., as part of a "whiplash" motion. In some circumstances, the viscoelastic properties of the suture may cause the suture to shatter. Therefore, movement of the suture lock (e.g., relative to the anchor) may be an additional source of potential failure of the mitral valve chordae tendineae repair system.

[0214] Furthermore, changes in tension on the sutures can alter the length of the artificial chordae, which can adversely affect the effectiveness of the artificial chordae, for example, in resolving MR. For example, as shown in FIGS. 49 and 50, when tension on the sutures is reduced or removed, the suture lock 4206 assumes a specific orientation relative to the sutures 4211 and 4244. In this situation, the artificial chordae have a specific length, for example, as measured between the valve leaflet (where the suture 4244 is connected to the leaflet) and the ventricular tissue (where the suture 4211 is secured to the anchor 4202). In effect, a portion of the suture (e.g., suture 4211) is wrapped around the suture lock 4206 and does not contribute to the overall length of the artificial chordae. However, when tension is applied to the sutures, the tension causes the suture lock 4206 to rotate, as shown in FIG. 50. As a result, the portion of the suture 4211 that was previously wrapped around the suture lock 4206 pulls away from the suture lock 4206, causing a corresponding increase in the length of the artificial chordae. In some circumstances, this increase is between about 0.10 mm and 0.30 mm, and in some cases 0.50 mm. In some embodiments, the amount of change depends on the width of the suture lock 4206 and the angle of rotation of the suture lock 4206. In some circumstances, these changes in length reduce the effectiveness of the artificial chordae, requiring the physician to readjust or reattach the artificial chordae.

[0215] Embodiments of the present disclosure are designed to mitigate the effects of some or all of these problems, while providing additional benefits that improve the effectiveness of artificial chordae and / or increase ease of implementation. For example, some embodiments include transcatheter mitral valve chordae repair systems designed to reduce or eliminate suture movement relative to suture locks and other system components. Additionally, certain embodiments act to reduce the amount of unconstrained sutures within the ventricle. Some embodiments provide artificial chordae incorporating artificial papillary muscles that can reduce the whiplash effect.

[0216] Certain embodiments are designed to limit or eliminate movement of the suture lock relative to the anchor, and these embodiments limit or eliminate movement of the suture relative to the anchor, at least in areas proximal to the anchor, thereby reducing suture wear and extending the life of the mitral valve chordae repair system.

[0217] In some embodiments, the transcatheter mitral valve chordae tendineae repair system uses a retention element, also referred to as a suture lock guide (e.g., a socket or sleeve), that limits the movement of the suture lock to form the prosthetic papilla structure. An example of such a suture lock guide was in the form of tubular sleeve 78, as described above with reference to FIGS. 2A and 2B. The movement of the sutures relative to the suture lock is also constrained near the suture lock, thereby reducing suture wear. In some embodiments, the transcatheter mitral valve chordae tendineae repair system includes a suture lock guide, also referred to as an anchor socket, that limits the movement of the suture lock relative to the anchor and the movement of the sutures relative to the suture lock.

[0218] Examples herein can provide prosthetic systems designed to maintain their integrity for approximately 800 million cycles or approximately 20 years. In certain embodiments, examples herein can provide prosthetic systems designed to maintain their integrity for approximately 800 million cycles or approximately 20 years. Artificial chordae are disclosed that can last for at least 400 million cycles or approximately 10 years. In certain embodiments, artificial chordae are disclosed that can last for at least 400 million cycles or approximately 10 years. These artificial chordae function under a variety of conditions and environments after 400 million cycles without undue structural damage and / or functional impairment, i.e., without holes, tears, gross delamination, cuts, fraying, incomplete leaflet cohesion, excessive reflux, etc.

[0219] 51 and 52 illustrate a transcatheter mitral valve chordae tendineae repair system 4300 according to some embodiments of the present disclosure. This system 300 provides one or more artificial chordae using one or more sutures or tethers deployed in a beating heart without extracorporeal circulation using a transcatheter delivery system. These embodiments use a retention or restraining member to reduce wear of the anchor sutures or tethers over time. In some embodiments, the retention or restraining member comprises a stent- or stent-graft-like socket secured to an epicardially placed fixation device or anchor. The delivery systems and techniques described above and / or disclosed in International Application Nos. PCT / US2017 / 069046 and PCT / US2019 / 021480 can be used to deliver the components of the system 4300 described above, which are incorporated by reference.

[0220] FIGS. 51 and 52 illustrate an anchor 4302, a retaining member 4304, and a suture lock 3406. In some embodiments herein, the retaining member 4304 is a socket or sleeve, similar to the sleeve 78 or socket described with reference to FIGS. 2A and 2B in certain aspects of the present disclosure. In other embodiments, the retaining member may be a pin, hook, clasp, prong, catch, buckle, suture, or the like. The anchor 4302 may be, in part or in whole, any of the anchors disclosed above and / or in International Application No. PCT / US2017 / 069046 or International Application No. PCT / US2020 / 021480. FIGS. 51 and 52 illustrate a suture 4308 and an anchor suture 4310. While FIGS. 51 and 52 show two sutures 4308, only one suture or more than one suture may be used. For example, sutures 4308 may be attached to one or more leaflets of the mitral valve using, for example, a pledget, using the systems or techniques described above and / or in International Application No. PCT / US2017 / 069046 or International Application No. PCT / US2020 / 021480. Thus, the sutures 4308 are referred to as pledget sutures. The anchor 4302 engages ventricular tissue, and the retention member 4304 can receive and secure the suture lock 4306 and sutures 4308, 4310.

[0221] The suture lock guide or retention member 4304, in some embodiments, facilitates placement, adjustment, and ultimately manipulation of the suture 4308 as part of the artificial chordae while limiting movement of the suture 4308 and / or suture lock 4306. For example, in some embodiments, the retention member (also referred to as a suture lock guide) 4304 is configured to be selectively coupled and decoupled from the suture lock 4306. When coupled to the suture lock 4306, the retention member 4304 provides a securement force strong enough to prevent slippage during the cardiac cycle (e.g., but not limited to, a force of up to about 1 N, 1.5 N, 2.0 N, 2.5 N, or 3 N), yet still allows the physician to pull on the suture 4308 to tighten or loosen the suture 4308 without displacing the suture lock 4306. In other embodiments, the retention member 4304 is designed to secure the suture 4308 and suture lock 4306, and to adjust the suture, the physician removes the suture lock 4306 from the retention member 4304, adjusts the suture 4308, and then reinserts the suture lock 4306 into the retention member 4304. Removing the suture lock from the retention member 4304 may require greater forces in certain embodiments, such as greater than about 6N to about 9N, or in some embodiments, greater than 10N. That is, in non-limiting embodiments, the retention member 4304 is configured to exert a retention force on the suture lock that resists forces of about 4N to at least 10N, including forces of about 4.5N, 5N, 5.5N, 6N, 6.5N, 7N, 7.5N, 8N, 8.5N, 9N, 9.5N, 10N, 10.5N, or 11N.

[0222] As a result of the retaining member 4304, the suture lock 4306 may maintain its positional relationship with the anchor 4302. For example, as cardiac tissue moves during the cardiac cycle, the retaining member 4304 resists a displacement force applied to the suture lock 4306 (e.g., via the suture 4308). In some embodiments, the retaining member 4304 transmits the force applied to the suture lock 4306 to the anchor 4302. The displacement force may be in a range of up to about 1 N, and in some cases, the displacement force may be about 1.5 N or up to about 3 N.

[0223] In some embodiments, the retention member 4304 is a socket formed by everting the vascular graft tube. The retention member 4304 is designed to be radially conformable so that the suture lock 4306 can be inserted into the retention member 4304 while still providing a restraining force. The retention member 4304 also has axial stiffness and is wear resistant. The axial stiffness allows the suture lock 4306 to be inserted into the retention member 4304 without buckling. Wear resistance is minimized by the PTFE-PTFE interaction.

[0224] 51 and 52, the retention member 4304 includes an inner surface 4330 that defines a chamber that receives and secures the suture lock 4306 and / or the suture 4308. In some embodiments, the retention member 4304 is formed from a material that is flexible enough to accommodate the suture lock 4306 and that allows adjustment of the suture 4308 relative to the suture lock 4306 even after the suture lock 4306 is inserted into the retention member 4304. In some embodiments, the retention member 4304 is radially conformable to allow the suture lock 4306 to be inserted and coupled with the retention member 4304. The retention member 4304 may be coupled with the suture lock 4306 using an interference fit, a frictional engagement, or the like.

[0225] In some embodiments, the retaining member 4304 couples with an outer surface of the suture lock 4306, for example, a portion of the outer surface located between the proximal and distal ends of the suture lock 4306. For example, the retaining member 4304 contacts opposite sides of the suture lock 4306 to couple with the suture lock 4306. In other embodiments, the retaining member 4304 contacts the suture lock 4306 at three or more points to inhibit movement of the suture lock 4306 relative to the anchor 4302. In FIGS. 51 and 52, the retaining member 4304 and suture lock 4306 are cylindrical, and the retaining member 4304 engages with the suture lock 4306 along or around its circumference. In FIGS. 51 and 52, the engaging contact between the retaining member 4304 and the suture lock 4304 extends longitudinally along the circumferential surface of the suture lock. In some embodiments, the engaging contact spans more than half of the longitudinal extent of the suture lock. In other embodiments, the engaging contact extends from about 20% to about 98% of the longitudinal extent of the suture lock. In other embodiments, the above ranges may be more limited, such as from about 40% to about 80%, from 50% to about 70%, or combinations of the above ranges (e.g., subranges of explicitly recited ranges).

[0226] 51 and 52 also illustrate a support member 4354 or support coil that reinforces the material of the retention member 4304 as it secures the suture lock 4306 and the suture 4308. In some embodiments, the anchor 4302 and the support member 4354 are two separate structures that may be integrated. In other embodiments, the anchor 4302 and the support member 4354 are integrally formed from a single material. The support member 4354 may extend along the length of the retention member 4304 such that it terminates in a position that is substantially aligned with the distal face of the suture lock 4306 when fully inserted into the socket 4304. In other embodiments, the support member 4354 extends along the length of the retention member 4304 such that it terminates in a position that is substantially aligned with an upper portion of the suture lock 4306 and below (or proximal to) the distal face of the suture lock 4306. The support member 4354 contacts the outer surface of the retention member 4304. An adhesive material 4362 is disposed along the exposed outer surfaces of the support member 4354 and the retention member 4304. This adhesive material 4362 may contact the exposed outer surface of the anchor hub 4338.

[0227] In some embodiments, the support member 4354 provides axial rigidity to prevent the suture lock 4306 from collapsing as it enters the retention member 4304. For example, in FIGS. 51 and 52 , the support member 4354 is a support coil that resists the longitudinal force exerted on the retention member 4304 by the suture lock 4306, for example, as the suture lock 4306 is forced into the retention member 4304. This additional rigidity keeps the retention member 4304 stable, thereby facilitating installation. In other embodiments, the retention member 4304 may be formed from other materials and may have other configurations. For example, the support member 4304 may be formed from multiple metal strips extending longitudinally along the outer surface of the retention member 4304, or one or more cylindrical cuffs spaced longitudinally along the other surface of the retention member 4304. In some embodiments, the retention member 4354 is a tine formed from nitinol or a similar material.

[0228] In some embodiments, the support member 4354 provides additional securing force to maintain the suture lock 4306 and suture 4308 within the retention member 4304. For example, in FIGS. 51 and 52 , the support member 4354 is a support coil. In some embodiments, when the suture lock 4306 is pressed into the retention member 4304, the support coil linearly compresses, expanding its inner diameter to accommodate the suture lock 4306. The compressive force of the support coil (e.g., upon recoil to its original configuration and smaller inner diameter) increases the frictional force between the retention member 4304 and the suture lock 4306. Furthermore, in some embodiments, the support coil is configured to linearly expand in response to a force pulling the suture lock 4306 from the retention member 4304. This further reduces the inner diameter of the support coil, increasing the frictional force between the retention member 4304 and the suture lock 4306.

[0229] In some embodiments, the support member 4354 terminates at an intermediate portion of the retention member 4304 below the distal portion of the retention member 4304. In this manner, the distal portion of the retention member 4304 above the support member 4354 exerts relatively less force on the suture lock 4306 and suture 4308 than the combination of the retention member 4304 and support member 4354. The relatively less force allows the physician to adjust the tension or length of the suture 4308 without displacing the suture lock 4306 from the retention member 4304.

[0230] In other words, in some embodiments, the retention member 4304 (alone or in combination with the support member 4354) provides sufficient force (e.g., between about 0 N and about 4 N of force) to retain the suture lock 4306 during the cardiac cycle. Force applied by the physician to the leaflets (e.g., pulling on the distal end of the suture 4308) and / or the suture 4308 (e.g., pulling on the proximal end of the suture 4308) allows the physician to adjust the suture 4308 relative to the suture lock 4306, which remains fixed within the retention member 4304 to adjust the length of the suture 4308 between the suture lock 4306 and the leaflet. In some embodiments, the force required to move the suture 4308 is between 1 N and 2 N. Thus, the retention member 4304 (alone or in combination with the support member 4354) secures the suture lock 4306 relative to the anchor 4302 during adjustment of the suture 4308. When the suture lock 4306 engages the suture 4308 (as described below), the retention member 4304 secures the suture lock 4306, thereby securing the suture 4308 as part of the prosthetic mitral valve chordae.

[0231] Continuing with reference to the embodiment described with reference to Figures 51 and 52, the retention member 4304 has a generally cylindrical structure. The retention member 4304 may be a stent or stent-graft structure formed (wholly or partially) from ePTFE. The material forming the retention member 4304 promotes tissue ingrowth to further secure the anchors 4302 and / or artificial chordae. The material forming the retention member 4304 includes a film microstructure with fiber orientation oriented substantially parallel to the longitudinal axis of the retention member 4304. In this manner, longitudinal movement of the suture 4308 (e.g., an ePTFE suture) matches the fiber orientation to further reduce friction and wear of the suture.

[0232] In other words, in some embodiments, the retention member 4304 is comprised of an ePTFE graft, an elastomer, another polymer, or a combination of these materials. For example, in some embodiments, the retention member 4304 is comprised of an ePTFE stretch graft, which may be densified to enhance column strength. In some embodiments, the retention member 4304 is partially or fully bioresorbable or bioabsorbable, providing temporary fixation until, for example, biological fibrous adhesion between tissue and other components occurs. In some embodiments, the retention member 4304 includes a mesh designed to enhance biocompatibility and fibrosis after implantation. All or a portion of the surface of the retention member 4304 may be configured to promote tissue growth on and / or through the surface. In one example, this growth is achieved by providing a relatively rough and / or porous surface. In another example, the material of the retention member 4304 may be perforated with one or more holes to allow scar tissue fibroblasts to grow through the holes, thereby enhancing fixation. Additionally, a biological coating of a type known in the art may be included on the surface of the retention member 4304 to promote healing and tissue growth.

[0233] The suture lock 4306 is secured within the retention member 4304 and is coaxially aligned with the anchor 4302. This configuration minimizes or eliminates relative movement of the suture lock 4306 with respect to the suture 4308, at least within the retention member 4304. This configuration also minimizes or eliminates movement of the suture 4308 within the retention member 4304 with respect to the suture lock 4306 and anchor 4302.

[0234] In some embodiments, the length of support member 4354 is between about 0.5 mm and 3.0 mm, while in other embodiments, the length of support member 4354 is between one-quarter the length of retaining member 4304 and the entire length of retaining member 4304.

[0235] Other embodiments (e.g., the embodiment shown in FIGS. 2A, 2B, and 55) do not include support member 4354. Some embodiments impart varying restraining forces through other mechanisms, such as varying the materials and / or surface treatments used to construct different portions of the socket or varying the size of the socket in different locations. Still other embodiments utilize an external tool to expand the upper portion of the socket or reduce the restraining force on the sutures and suture locks in the upper portion.

[0236] 52, the suture 4308 can be disposed between the outer surface of the suture lock 4306 and the inner surface of the retention member 4304. In some embodiments, these surfaces (in whole or in part) are designed to facilitate securement of the suture 4308, e.g., have a higher coefficient of friction. In other embodiments, these surfaces (in whole or in part) are designed to facilitate easy adjustment of the suture 4308, e.g., have a lower coefficient of friction. One or both of these surfaces can be resilient to aid in securement of the suture 4308 while still allowing adjustment.

[0237] Securing the sutures 4308 between the suture lock 4306 and the retention member 4304 provides additional benefits. For example, even if tension on the proximal portion of the suture (e.g., the portion extending from the socket 4306 to the physician or the proximal end of the catheter) is varied or removed, the suture lock 4304 and retention member 4304 maintain logarithmic tension on the distal portion of the suture (e.g., the portion extending from the suture lock 4306 to the valve leaflet). As a result, once the suture lock 4306 is positioned within the retention member 4304, thereby securing the sutures 4308, tension changes on the proximal portion of the suture (e.g., if the physician accidentally bumps the catheter) do not substantially affect the tension on the distal portion of the suture 4308. Thus, the physician does not need to maintain tension on each suture 4308 during surgery. Additionally, in some embodiments, a suture lock 4306 and retaining member 4304 may be used to maintain tension on the distal portion of one suture while adjusting the other suture.

[0238] As shown in FIG. 52 , in some embodiments, the retention member 4304 has an upper enlarged portion 4376 and a lower enlarged portion 4378. These enlarged portions 4376, 4378 provide additional axial stiffness to prevent folding or buckling when the suture lock 4306 is pressed into the retention member 4304. Additionally, the upper enlarged portion 4376 can incorporate a band to provide additional stiffness and a radiopaque marker. In some embodiments, the upper enlarged portion 4376 includes an outer surface that is located further outward (e.g., radially) than the lower portion of the socket. The upper enlarged portion 4376 has an inner surface that is located further outward (e.g., radially) than the lower portion of the retention member 4304. For example, the upper enlarged portion 4376 can be tapered (e.g., funnel-shaped) to aid in receiving the suture lock 4306.

[0239] The sutures 4308, 4310 may be formed from a surgical-grade material, such as a biocompatible polymeric suture material. Examples of such materials include 2-0 ePTFE (polytetrafluoroethylene) or 2-0 polypropylene. In some embodiments, the sutures 4308, 4310 are inelastic. In other embodiments, the sutures 4308, 4310 are partially or fully elastic. In some embodiments, the sutures 4308, 4310 are partially or fully bioresorbable or bioabsorbable, for example, to provide temporary fixation until biological fibrous adhesion between tissue and other components occurs. Thus, the sutures 4308, 4310 may be formed from a biocompatible material (e.g., nitinol, ePTFE, PTFE, PET, or polyester, nylon, silicone, collagen or other amino acid proteins, stainless steel, cobalt chrome, combinations thereof, etc.).

[0240] 51 and 52 show an anchor hub 4338 that contacts the cardiac tissue 4352 and serves as a stopping point for the anchor 4302 as it is threaded into the cardiac tissue. In some embodiments, the anchor hub 4338 includes an upper surface that is coupled to the bushing 4353 (as described below). The anchor 4302 and anchor hub 4338 are joined together via mechanical, chemical, or other means, such as frictional engagement. The anchor hub 4338 transfers forces applied to the retention member 4304 through the anchor 4302 (e.g., via sutures 4308) to the cardiac tissue 4252. In this manner, the anchor hub 4338 interfaces with the retention member 4304 to dampen vibrational motion caused by cardiac movement.

[0241] In some embodiments, the proximal surface of the anchor hub 4338 contacts the suture lock 4306 (e.g., the nose of the suture lock 4306) and the suture 4308. The anchor hub 4338 (or at least its proximal surface) may be formed from a material designed to increase friction to secure the suture 4308 disposed between the anchor hub 4338 and the suture lock 4306, or alternatively, may be formed from a material that reduces friction to facilitate adjustment of the suture 4308 disposed between the anchor hub 4338 and the suture lock 4306. The anchor hub 4338 is formed from PFA, a silicone material, a PTFE material, an ePTFE material, a thermoplastic, or the like (or a combination thereof). In some embodiments, the anchor hub 4338 is formed partially or entirely from metal, stainless steel, titanium, a hard plastic such as PEEK, or other sufficiently rigid material. The proximal face or bushing of the anchor hub 4338 that interacts with the suture lock is formed from PFA, a silicone material, a PTFE material, an ePTFE material, a thermoplastic, or the like (or a combination thereof).

[0242] In some embodiments, the bushing 4353 is disposed adjacent the anchor hub 4338 to mitigate cushioning of the suture lock 4306. The bushing may be formed from PFA or another polymer. The bushing provides a surface that contacts the suture 4308 and, in combination with the nose portion of the suture lock 4306, aids in securing the suture 4308. In some embodiments, the bushing facilitates suture adjustment due to the interaction of the PFA material of the bushing with the ePTFE material of the suture 4308. The bushing may also provide a surface that reduces suture wear, particularly if the anchor hub 4338 presents a rougher surface to the suture 4308 (e.g., due to the material and / or surface of the anchor hub 4338). The bushing 4353, or the proximal surface of the anchor hub 4338 that interacts with the suture lock, may be formed from PFA, a silicone material, a PTFE material, an ePTFE material, a thermoplastic, or the like.

[0243] In some embodiments, the diameter of the hub (e.g., hub 4338) corresponds to the minor or inner diameter of the support member 4354. Depending on how it is attached, the length of the hub 4338 is long enough to attach the support member 4354 to the hub 4338 and to allow a driver to engage the hub 4338. The shape in which the retaining member 4304 is attached to the hub 4338 is smaller than the minor diameter of the support member 4354. In some embodiments, the outer diameter of the retaining member 4304 is smaller than the diameter of the support member 4354.

[0244] 52 , the anchor sutures 4310 may pass through channels 4336 in the anchor hub 4338 and be secured near a bottom surface 4340 of the anchor hub 4338. In some embodiments, the channels 4336 include bottlenecks 4342 that secure the anchor sutures 4310 (e.g., by capturing a knot formed at the end of the anchor suture 4310 below the anchor suture 4342). In other embodiments, the anchor sutures 4310 and the anchor hub 4338 are coupled together by mechanical means, such as a friction fit, chemical means, or other similar means.

[0245] The suture lock 4306 may include features of the suture locks described herein and / or disclosed in International Application Nos. PCT / US2017 / 069046 and PCT / US2019 / 021480. The suture lock 4306 has a cylindrical outer surface that corresponds to the cylindrical chamber of the retention member 4304 to provide a frictional engagement or interference fit. The suture lock 4306 may include a locking mechanism (e.g., an internal locking mechanism) that selectively secures the anchor suture 4310 and the suture 4308. The illustrated suture lock 4306 includes a nose portion 4370 that provides a rounded surface against which the suture presses when tension is applied. In this manner, the suture lock 4306 avoids sharp edges that could fray the suture 4308. In some embodiments, the nose portion 4370 is formed, for example, from PFA or other material designed to reduce suture wear.

[0246] The suture lock 4306 moves down the anchor suture 4310 until it enters the cylindrical chamber of the retention member 4304. The retention member 4304 provides some radial resistance to the suture lock 4306 but conforms radially to receive the suture lock 4306. In some embodiments, the suture 4308 can be adjusted even when the suture lock 4306 is in its lowest position (i.e., down to the end of the socket 4304, which involves pressing the bushing 4353). For example, the suture 4308 is most easily adjusted while the suture lock 4306 is outside of the retention member 4304. However, the suture 4308 can still be adjusted even after the suture lock 4306 enters the retention member 4304. In some embodiments, when the suture lock 4306 is in its lowest position, the suture 4308 is sandwiched between the PFA bushing 4353 and the PFA nose 4370 of the suture lock 4306. In some embodiments, at this stage, the suture 4308 can still be adjusted, albeit with greater resistance. For example, the suture lock nose 4370 and bushing 4353 reduce friction for easier adjustment. In other embodiments, the bushing 4353 and nose 4370 are otherwise designed to secure the suture and prevent further movement.

[0247] In some of the embodiments described above, the anchor 4302 is pre-assembled with the retention member 4304. In other words, the anchor 4302 and retention member 4304 are coupled together outside the patient's body. The suture lock 4306 is then coupled to the retention member 4304 inside the patient's body (e.g., via a frictional engagement or an interference fit). In other embodiments, the retention member 4304 and the suture lock 4306 are coupled together outside the patient's body. The retention member 4304 and the anchor 4302 are then coupled to one another inside the patient's body (e.g., via a frictional engagement or an interference fit).

[0248] In some embodiments, the retention member 4304 is configured to expand. For example, in some embodiments, the retention member 4304 is formed from a resilient material that expands when the suture lock 4306 is pressed down onto the retention member 4304, helping to reseal around the suture lock 4306 and secure it in place. In other embodiments, the retention member 4304 has an expanded configuration and a retracted (contracted) position. The retention member 4304 is delivered in the expanded configuration, and once the suture lock 4306 is in place, the retention member 4304 folds into the retracted position to secure the suture lock 4306 in place.

[0249] 53 , the anchor 4402 defines a longitudinal line 4403, and a retaining member 4404 or restraining member (e.g., a socket) restrains movement of the suture lock 4406 relative to the anchor 4402 in a direction perpendicular to the longitudinal line 4403 defined by the anchor 4402. In some embodiments, the retaining member 4404 restrains movement of the suture lock 4406 relative to the anchor 4402 in a plane perpendicular to the longitudinal line 4403. In some embodiments, the retaining member or restraining member (e.g., a socket 4404) restrains movement of the suture lock relative to the anchor along the longitudinal line 4403.

[0250] 53 , the restraining member 4404 substantially aligns the longitudinal line 4403 defined by the anchor 4402 and / or the longitudinal line 4405 defined by the restraining member 4404 with the longitudinal line 4407 defined by the suture lock 4406. In some embodiments, the retention member 4404 secures the suture lock 4406 in a coaxial relationship with the anchor 4402 and / or the retention member 4404. In some embodiments, the longitudinal line defined by the anchor 4402, the retention member 4404 and / or the suture lock 4406 extends to the leaflets of the mitral valve.

[0251] In some embodiments, as shown in FIG. 54 , the retention member 4504 constrains angular movement of the suture (suture 4511) relative to the suture lock 4506. As discussed above with reference to FIGS. 49 and 50 , in some embodiments, the suture lock rotates in response to forces during the cardiac cycle, resulting in significant variations in the angle formed by the portion of the suture extending from the suture lock toward the valve leaflet relative to a longitudinal line defined by the suture lock. The location of the suture lock above the anchor and close to the valve leaflet also contributes to angular movement. However, as shown in FIG. 54 , the retention member 4504 constrains angular movement of the suture 4511 by fixing the suture lock 4560 in a particular orientation. For example, in some embodiments, the angle 4520 formed between the portion of the suture 4511 extending from the suture lock 4506 toward the valve leaflet and the longitudinal line 4522 of the suture lock 4506 is less than 45°. In some embodiments, angle 4520 ranges from approximately -45° to +45°, which ranges from approximately 0° to 45° in two opposite directions. This angle 4520 can be formed in any plane that contains the portion of suture 4511 and the longitudinal line 4522 of the suture lock.

[0252] Although the suture 4511 moves during the cardiac cycle, the retention member 4504 can limit the angular movement (change in angle 4520) to less than 90°. In some embodiments, the angular change is less than 45°, and in other embodiments, the angular change is less than about 40°, 35°, 30°, 25°, 20°, 15°, 10°, 8°, or less than about 5°.

[0253] A method for measuring the change in angle between the ventricular anchor and the suture lock is described.

[0254] The angular change between the anchor and the suture lock is determined, for example, by the following steps:

[0255] 1. Secure the ventricular anchor to one side of the tensile tester. This can be done by simulating ventricular anatomy, such as a silicone pad, or by clamping it into the jaws of a standard tensile tester clamp.

[0256] 2. Secure the artificial chordae to the other side of the tensile tester. This can be done by simulating a valve leaflet structure, such as a silicone pad, or by clamping it into the jaws of a standard tensile tester clamp.

[0257] 3. Use a suture lock to connect the ventricular anchor to the artificial chordae.

[0258] 4. The system including the ventricular anchor, artificial chordae and suture lock is loaded with a minimum tension of 2N.

[0259] 5. Measure the angle between the axis of the suture lock or any linear feature of the suture lock and the axis of the ventricular anchor or any linear feature of the ventricular anchor (Angle 1).

[0260] 6. Unload the system including the ventricular anchor, artificial chordae and suture lock to a load less than 0 N or a load equivalent to the static weight of the system hanging from the load cell.

[0261] 7. Measure the angle between the axis of the suture lock or any linear feature of the suture lock and the axis of the ventricular anchor or any linear feature of the ventricular anchor (Angle 2).

[0262] 8. Calculate the difference between angle 1 and angle 2.

[0263] During placement of the artificial chordae, the anchor and retention member are delivered (e.g., via a catheter) and the anchor is implanted into the ventricular tissue. Anchor sutures extend from the anchor. Sutures (e.g., pledget sutures) are then attached to one or more mitral valve leaflets. A suture lock advances the anchor sutures and pledget sutures. In some embodiments, the physician can adjust the position of the suture lock relative to the pledget sutures so that the length of the pledget suture between the suture lock and the leaflet ensures proper operation of the artificial chordae (e.g., to reduce and / or eliminate MR). For example, the physician pulls a proximal portion of one suture to reduce the amount of suture located between the suture lock and the mitral valve leaflet.

[0264] However, in certain embodiments, the suture lock is not restricted. As a result, adjusting the suture (e.g., pulling the suture) moves the suture lock upward, which affects the tension of the suture portion between the suture lock and the mitral valve. This problem can be exacerbated when multiple sutures are used with the suture lock. Adjusting one suture raises the suture lock, undoing previous adjustments of other sutures.

[0265] For example, sutures can be attached to the valve leaflets and pass through a suture lock, which acts as a movable pulley for the suture. Specifically, when a physician pulls on the end of the suture located outside the body, the suture moves. However, pulling on the proximal end of the suture can cause the suture lock to move upward, so the physician's movement relative to the suture located outside the body does not correspond one-to-one with the movement of the suture between the suture lock and the valve leaflets.

[0266] This problem can be exacerbated when multiple sutures pass through a single suture lock. For example, a physician may adjust the first suture to the correct length. However, when the physician begins to adjust the second suture, this movement displaces the suture lock. This can adversely affect the first suture, requiring the physician to use force to readjust the first suture. This can adversely affect the second suture, requiring additional adjustment.

[0267] If the physician cuts the sutures after engaging the suture lock, additional problems arise. Before cutting the sutures, the physician maintains tension on the suture, which keeps the suture lock in a higher position. Cutting the sutures (and / or disconnecting the suture lock from the catheter) releases the tension and can cause the suture lock to move downward, which can affect the effectiveness of the sutures as artificial chordae. The physician must maintain tension on the sutures (e.g., the first suture) while adjusting the second suture, which creates additional problems. For example, inadvertent movement of the catheter (e.g., accidental bumping) can cause the suture lock to move, changing the length of the suture between the suture lock and the tissue (e.g., a valve leaflet).

[0268] Some embodiments described herein address this problem by securing the suture lock within a retention member, thereby creating a pivot point for the suture that is stationary relative to the anchor. This is particularly beneficial when the physician adjusts the suture during creation of the artificial chordae. By securing the suture lock to the anchor (e.g., with a retention member), upward movement of the suture lock during adjustment can be substantially eliminated.

[0269] Furthermore, having a stationary pivot point allows for a more direct correlation between adjusting the proximal portion of the suture (i.e., pulling the part of the suture closest to the physician) and the resulting adjustment of the distal portion of the suture (i.e., the part of the suture between the suture lock and the mitral valve). In particular, many of the embodiments described herein allow for bidirectional, precise suture adjustment, whereby movement of the guide device (e.g., catheter) translates into a change in the length of the suture between the valve leaflet and the suture lock, for example. For example, moving the guide device forward 1 mm also moves the suture forward 1 mm. This is referred to as "one-to-one motion." As those skilled in the art will readily appreciate from this disclosure, some embodiments herein allow for one-to-one or near one-to-one motion under a variety of conditions. In particular, International Application Nos. PCT / US2017 / 062014 and PCT / US2019 / 021400, both of which are incorporated herein by reference, disclose mechanisms for making sutures "pushable." This includes by placing a stiff tubular structure (i.e., a coil) at the suture. The stiffness provided by the coil allows the suture to be pushed like a cardiac guidewire. In this regard, the movement of the modified suture follows the movement of the guide device (e.g., a catheter or coil) "one-for-one."

[0270] In other words, securing the suture lock within the retention member creates a fixed pivot point for the suture, such that movement by the physician relative to the suture located outside the body has a one-to-one correspondence with the movement of the suture between the suture lock and the valve leaflet. As those skilled in the art will readily appreciate, in some circumstances, the one-to-one movement may be reduced to approximately one-to-one movement due to other variables (e.g., slight stretching of the suture or small movements of the suture lock) that differ significantly in nature and extent from the suture lock movement at issue in the non-limiting examples. For example, the movement ratio (movement ratio) may vary from 1:1 to about 1:0.95, 1:0.90, 1:0.85, 1:0.80, etc., up to 1:0.50.

[0271] Creating a fixed pivot point with the suture lock provides additional benefits. For example, when multiple sutures are passed through the suture lock, each suture can be adjusted independently without substantially affecting the other sutures. In particular, with the suture lock fixed within the retention member, a first suture can be adjusted to the correct length. Because the suture lock does not move with the second suture, the surgeon can begin adjusting the second suture without interfering with the adjustment of the first suture.

[0272] Additionally, in some embodiments, a portion of the first suture is located between the outer surface of the suture lock and the inner surface of the socket. As the physician adjusts the second suture, the force provided by the surface holds the portion of the first suture in place. This configuration provides an additional benefit because the physician does not need to maintain external tension on the first suture. Reducing or eliminating tension on the suture can reduce suture stretching or other deleterious effects.

[0273] Furthermore, the first suture can be cut without changing the position of the suture lock and without changing the length of the suture between the suture lock and the tissue. One skilled in the art will understand that in this context, there may be slight movements (e.g., less than 5 / 1000 inch or less than 5 / 100 inch) that are considered less than a substantial change in position.

[0274] Additionally, in some embodiments, the suture lock serves as a fixed pivot point located near the tissue in the target area (eg, near the apex of the heart), thereby facilitating attachment.

[0275] In some embodiments, multiple sutures are attached to tissue (e.g., one or more valve leaflets) and passed through the suture lock. Each suture has a length extending between the suture lock and the tissue. When the suture lock is placed in the retention member, the sutures are held in place. When it is necessary to adjust a first suture (e.g., to decrease the length of the first suture between the suture lock and the tissue), the suture lock is removed from the retention member, and the physician pulls the first suture to decrease its length. However, during this adjustment, the position of the suture lock remains relatively stationary (e.g., the suture lock moves within 1 mm). Therefore, the physician does not need to further adjust or readjust other sutures. In some embodiments, the suture can be adjusted while the suture lock is within the retention member. The retention member secures the suture lock, further reducing or eliminating movement of the suture lock during suture adjustment. For example, the suture lock moves by approximately 0.5 mm or less.

[0276] In some embodiments, the suture lock engaged by the retention element is sufficiently loose so that the force of the leaflets on the suture (e.g., ePTFE chordae) is sufficient to pull the suture through the interface between the suture lock and the retention element, around the nose of the suture lock, through the open clamp mechanism of the suture lock, and back into the pushable portion of the suture assembly. The manageable force in this situation ranges from 0 N to about 2 N. In some embodiments, the force is between 0.15 N and 1.50 N.

[0277] In some embodiments, the physician pulls the outer portion of the suture to shorten the length of the suture between the suture lock and the valve leaflet. When the physician wants to lengthen the length of the suture between the suture lock and the valve leaflet, the physician releases tension on the outer portion of the suture, and the movement of the valve leaflet during the heart's natural cardiac cycle allows the suture to be pulled. In some embodiments, the suture lock is positioned on a first portion of the retention member. In this position, the force acting on the suture is small enough (e.g., 0N to 2N force) that the physician and the valve leaflet can cause a change in the length of the suture between the suture lock and the valve leaflet. At the same time, the securing force exerted by the retention member prevents the suture lock from moving during the adjustment or limits the movement of the suture lock to approximately 0.5 mm.

[0278] In some embodiments, once the length of the suture between the suture lock and the corresponding tissue is corrected (e.g., MR is clinically reduced or eliminated), the suture lock is pushed into the second portion of the retention member. In this position, the retention member applies a greater fixation force to the suture lock and the suture. As a result, the suture does not move within the suture lock (or moves slightly, e.g., about 0.5 mm) due to the force exerted by the valve leaflets, so that the length of the suture between the suture lock and the tissue remains constant (or moves only by the amount of stretch exerted by the suture, e.g., about 10%). At this point, the physician can perform an analysis measuring the tension and placement exerted by the artificial chordae. If the analysis is satisfactory, the physician engages the suture lock to secure the suture. In this configuration, the artificial chordae can be used for at least 400 million cycles, i.e., about 10 years, or 8 million cycles, or about 20 years. In certain embodiments, in this configuration, the artificial chordae can be used for at least 400 million cycles, or 10 years, or 8 million cycles, or 20 years.

[0279] In some embodiments, the sutures are permanently secured using only the restraining force of the retention member, either alone or in combination with the outer surface of the suture lock. For example, the suture lock may lack an internal clamp or restraining mechanism and, together with the inner surface of the retention member, provide an outer surface that secures the sutures against further movement from forces resulting from the heart's natural cardiac cycle.

[0280] In some embodiments, the retention member allows the suture lock to work with sutures of various sizes. For example, larger and / or thicker sutures are secured when the suture lock is inserted into a first portion of the retention member. Smaller sutures can also be secured by, for example, forcing the suture lock deeper into the retention member.

[0281] Embodiments of the present disclosure provide the additional benefit of easily adjustable sutures. Friction can make suture adjustment difficult, as well as reducing the life and effectiveness of the suture. Some embodiments address this issue by using a suture lock with a tapered nose. For example, as shown in FIG. 52 , the distal end of the suture lock 4306 has a tapered nose 4370. The outer surface of the suture lock 4306 is cylindrical, and similarly, the outer surface of the nose 4370 has a cylindrical shape with a decreasing radius toward the distal end of the nose 4370.

[0282] The front surface of nose portion 4370 has an inner opening surrounded by a tapered nose ring. In some embodiments, the diameter of the inner opening is between 1 mm and 3 mm. The thickness of the ring is between 0.5 mm and 2.0 mm.

[0283] The tapered nose 4370 facilitates insertion of the suture lock 4306 into the retention member 4304. In some embodiments, the nose 4370 has a sharper taper (tapes more rapidly), while in other embodiments, the nose 4370 has a gentler taper (tapes less rapidly). Additionally or alternatively, the retention member 4304 includes a proximal portion that tapers outward to guide the suture lock 4306 into the interior portion of the retention member 4304. For example, the proximal end of the retention member 4304 may have a larger radius than the middle portion of the retention member 4304. As previously described, an anchor suture 4310 may be used to guide the suture lock 4306 into the retention member 4304.

[0284] 52, the inner surface of the nose 4370 includes a proximal portion that increases in thickness from the anterior portion to the middle portion along a longitudinal axis. After the middle portion, the thickness of the nose decreases toward the distal portion. In some embodiments, the proximal end of the nose can be configured to snap fit onto a suture lock body.

[0285] To facilitate bidirectional adjustment, certain embodiments ensure reduced friction on the sutures via the suture lock and retention members. For example, the nose profile provides a rounded surface that facilitates drawing sutures around the nose without creating sharp edges that can abrade the sutures. Additionally, the nose composition may include, for example, PFA or other materials that further reduce friction between the sutures and the nose.

[0286] The nose can be configured to accommodate multiple sutures simultaneously. At the same time, the tapered profile allows for easy access to the retention member. To utilize both of these functions, the size of the opening in the nose corresponds to the number of sutures used. For example, if two sutures are used, the diameter of the nose opening is 1 mm, and if four sutures are used, the diameter of the nose opening is 2 mm. Typically, the ratio of diameter to number of sutures is about 0.5 mm per suture. In some embodiments, multiple different noses (e.g., noses with different sized openings) can be used interchangeably with a single suture lock body. In other embodiments, the size of the suture lock (e.g., the diameter of the suture lock) can be increased or decreased to accommodate different numbers of sutures.

[0287] In some embodiments, the film microstructure is formed of ePTFE material with the fibril orientation oriented in a direction substantially parallel to the longitudinal axis of the retention member. In this manner, longitudinal movement of a suture (e.g., an ePTFE suture) follows the fibril orientation to further reduce friction and wear of the suture. For example, in some embodiments, the retention member (either entirely or at least on the interior surface) is formed from a substantially monolithic ePTFE covering having a node and fibril microstructure. The nodes are oriented substantially perpendicular to the longitudinal axis of the retention member, and the fibrils are substantially parallel to the longitudinal axis of the retention member.

[0288] As previously described, the retaining member engages the sutures and / or the suture lock. In some embodiments, to allow slack in a suture, the suture lock must be disengaged from the retaining member. This simplifies maintaining tension in one suture relative to the other sutures because there is no longer a change in length that occurs through the catheter. In these embodiments, to allow slack in a suture, the suture lock is disengaged from its interference fit with the retaining member. In other words, in some embodiments, multiple sutures pass through the suture lock, which is inserted into the retaining member. As a result, the sutures are held in place between the outer surface of the suture lock and the inner surface of the retaining member. If the physician needs to adjust one suture, the suture lock is disengaged from the retaining member. At this stage, the suture in question can be adjusted without significantly moving the suture lock upward. Therefore, adjusting the suture does not significantly change the tension in the other sutures.

[0289] In some embodiments, the retention members function as artificial papillary muscles as part of the artificial chordae tendineae. For example, the materials of the retention members and sutures (and anchors and / or suture locks) are selected to promote tissue encapsulation, tissue ingrowth, and / or a specific biological response.

[0290] FIG. 55 illustrates another embodiment of a transcatheter mitral valve chordae tendineae repair system 4600. This system 4600 has similar features to those shown in FIGS. 51 and 52. However, in this embodiment, the retention member 4604 does not include a support member. Instead, the anchor 4602 extends around the anchor hub 4638 and terminates at the underside of the retention member 4604. A mechanical bond or joint 4601 secures the retention member 4604 to the anchor hub 4638. The anchor 4602 and anchor hub 4638 may be coupled to each other as previously described. In FIG. 55, the walls of the retention member 4604 are 25% to 100% thicker than the walls of the socket in FIGS. 51 and 52. The thicker walls provide axial support to prevent buckling as the suture lock 4606 enters the retention member 4604, while maintaining sufficient compliance to allow passage. A mechanical bond or joint secures the anchor hub 4638 to the retaining member 4604 which extends across the anchor hub 4638 .

[0291] Some embodiments include a method of transcatheter mitral valve chordae tendineae repair using a transcatheter mitral valve chordae tendineae repair system. During this process, the anchor and anchor socket are delivered together, for example, via a delivery catheter. FIGS. 56-58 illustrate a method of delivering the anchor 4702, socket 4704, and suture lock 4706. In FIG. 56, the anchor 4702 is positioned within the socket 4704. In this configuration, both the anchor 4702 and the socket 4704 pass through the catheter and into the left ventricle (e.g., via the left atrium). In some embodiments, the anchor 4702 is fully retracted (sealed) within the socket 4704 to prevent the anchor 4702 from contacting or puncturing the catheter or other tissue. Once the socket 4704 is positioned against the ventricular wall, the anchor 4702 is advanced from the socket 4704 into the tissue. As the anchor 4702 emerges from the socket 4704, the socket attachment device 4755 captures the coil threads until it finally contacts the anchor hub 4738 to lock the anchor 4702 in place. In some embodiments, the socket attachment device 4755 is a suture with a loop or series of loops through which the coil passes. In other embodiments, the socket attachment device 4755 is an extension of the socket material at the distal end of the socket 4704, the extension having a hole or series of holes through which the coil passes. In both of these examples, pushing the coil through the holes or loops advances the coil until the socket attachment device 4755 is secured relative to the anchor hub 4738.

[0292] FIG. 57 shows the anchor 4702 and socket 4704 as the anchor 4702 is deployed within ventricular tissue. The socket attachment device 4755 secures the anchor hub 4738 (and therefore the anchor 4702) in place relative to the socket 4704. The suture lock 4706 is then advanced through the socket 4704 along with the anchor suture 4710 until it contacts the bushing 4753, as shown in FIG. 58. Once the suture 4708 is properly tensioned, the suture lock 4706 is actuated, locking the suture 4708 and anchor suture 4710 in place. The suture lock 4706 is coaxially aligned with the anchor 4702 and parallel to the suture 4708, which is pinned between the outer surface of the suture lock 4706 and the inner surface of the socket 4704. Additionally, the suture 4708 is pinned between the curved nose of the suture lock 4706 and the bushing 4753 .

[0293] 59 and 60 illustrate another embodiment of a transcatheter mitral valve chordae tendineae repair system 4800. This system has similar features to that shown in FIGS. 51 and 52. In this embodiment, an anchor pledget 4860 is incorporated into the anchor suture 4810. When the suture lock 4806 is advanced into the socket 4804, the anchor pledget 4860 collapses to form a bushing between the anchor hub 4838 and the suture lock 4806. The suture lock 4806 selectively engages the sutures 4808, which are coupled with the leaflets and the remainder of the anchor suture 4810.

[0294] FIG. 61 shows a socket formed from densified ePTFE 4850. In some embodiments, the socket is formed from ePTFE. The socket is formed in two layers by folding the tube over. This reinforces the socket to resist axial compression and folding when the suture lock enters the socket. In some embodiments, the retention member is formed from a thick-walled graft material. To increase axial stiffness, the thick-walled graft material is densified (compressed). An example of this is shown in FIG. 61, where the graft material has been rolled (rolled) to achieve the appropriate thickness and density. Furthermore, the resulting two-layer structure provides increased flexibility through densification.

[0295] FIG. 62 shows a "rolled" end 4852 of a PTFE socket. In some embodiments, the socket is formed from ePTFE. A marker band 4854 is placed on the exterior surface of the tubing before it is rolled, and a band is placed between the two rolled layers at the top of the socket. This band is radiopaque. In some embodiments, the retention member includes an end portion with a different radial stiffness than the rest of the retention member. For example, the proximal portion of the retention member can be formed to have a higher radial stiffness. In some embodiments, as shown in FIG. 62, a marker band is placed between the layers of graft material as it is rolled to form the retention member. This marker band adds radial stiffness and makes this portion of the retention member radiopaque. In some embodiments, the marker band is held between two layers of PTFE or ePTFE and densified into the PTFE or ePTFE structure.

[0296] FIGS. 63 and 64 show a densified PTFE socket 5004 designed to interface with an anchor hub 5016. In some embodiments, the socket 5004 is formed from ePTFE. The densified PTFE or ePTFE socket 5004 includes a downward extension 5070 that fits into a corresponding groove 5072 in the anchor hub 5016, thereby securing the socket 5004 to the hub 5072. A radiopaque band 5074 is located near the top of the socket 5004. The densified PTFE or ePTFE can be used to retain the anchor. As shown in FIG. 63, the PTFE or ePTFE is pressed into the anchor's retaining ring to hold the anchor in place. FIG. 64 shows an exemplary retention member with a marking band incorporated into the proximal portion and a densified portion with a distal portion designed to retain the anchor (not shown in FIG. 64).

[0297] Figures 65A and 65B show a socket in which a vascular graft tube is everted to form the outer and inner walls, thereby forming a socket from a biocompatible material. This material may be the same as the suture material, thereby minimizing or reducing abrasion of the sutures where they reside in the socket. The fibril orientation of the socket surface is oriented to match the fibril orientation of the sutures to minimize abrasion.

[0298] The various artificial chordae deployment systems described above can be used in many different medical applications. According to the above embodiments, movement of the suture relative to the suture lock and movement of the suture lock relative to the anchor can be reduced or eliminated. For example, in some embodiments, an anchor is delivered to cardiac tissue, e.g., near the apex of the left ventricle or near the papillary muscles. As previously described, the anchor is delivered through a transseptal catheter advanced into the left atrium and through the left atrium and mitral valve. The anchor is a helical anchor and is coupled to a retention member. In some embodiments, the anchor is first delivered into the retention member and then advanced from the retention member into the cardiac tissue. Anchor sutures are attached to the anchor (e.g., via an anchor hub). Leaflet anchors (e.g., pledgets) are then delivered and attached to the leaflets of the mitral valve. In some embodiments, the pledget is located on the ventricular side of the leaflet with the pledget sutures extending from the atrial side of the leaflet. In other embodiments, the pledget is located on the atrial side of the valve leaflet and the pledget sutures extend from the ventricular side of the valve leaflet. Multiple pledgets and sutures may be placed on one or more valve leaflets.

[0299] In certain embodiments, the suture lock is advanced over the anchor suture and suture to affect the artificial chordae. Specifically, the proximal end of the suture enters through an opening in the suture lock and passes through the suture lock. The suture lock is advanced toward the retention member, guided by the suture anchor. Because the suture lock is radiopaque and the retention member may include a radiopaque band near its proximal surface, a physician can use imaging techniques to confirm the position of the suture lock relative to the retention member. Additionally, the use of a radiopaque band on the retention member allows a physician to confirm that the suture lock is fully inserted into the retention member.

[0300] In certain embodiments, once the suture lock reaches the retention element, the physician adjusts the length of the suture between the suture lock and the valve leaflet to affect the new artificial chordae. In some embodiments, some or all of the adjustments are made at the suture lock at or within the retention element. In certain embodiments, because the suture lock is maintained in a relatively constant position at the retention element, any movement of the suture results in a one-to-one or near one-to-one movement of the suture distal to the suture lock. For example, the ratio of proximal suture movement to distal suture movement can be between 0.5 and 1.0.

[0301] In some embodiments, this adjustment is made using a suture lock just outside of the retention member, with the physician holding the suture lock in place and holding the suture in tension. In other embodiments, this adjustment is made using a suture lock on the retention member (either the proximal portion of the retention member or the distal portion of the retention member adjacent the anchor hub). In such embodiments, the retention member holds the suture lock in place but allows the suture to slide through the suture lock. The physician does not need to hold the suture lock in place.

[0302] Furthermore, in some embodiments, the restraining force of the retention member is sufficient to hold the sutures in place against forces exerted by the valve leaflets, yet still allow the sutures to slip in response to pulling forces from the physician. In these embodiments, the physician does not need to hold the suture lock in place, nor does the physician need to hold each suture in tension. Instead, the retention member maintains tension on the distal portion of the pledget suture (i.e., the portion of the pledget suture that is distal to the retention member and extends to the valve leaflet). This allows the physician to adjust each pledget suture individually, and inadvertent movement of the catheter (such as accidental bumping) will not affect the sutures. The physician's adjustment in this situation is unidirectional (i.e., shortening the length of the suture between the suture lock and the pledget). If the physician needs to lengthen the length of the suture between the suture lock and the pledget, the physician removes the suture lock from the suture so that movement by the valve leaflet will again pull the suture through the suture lock.

[0303] Once the sutures are properly tightened, the physician can lock the sutures in place using a suture lock, such as the techniques disclosed herein and / or in International Application Publication Nos. PCT / US2017 / 069046 and PCT / US2019 / 021480. In other embodiments, the retention member locks the sutures in place without the need for an additional locking mechanism within the suture lock. The physician then cuts the excess suture (e.g., the suture located proximal to the retention member). Because the sutures are no longer under tension proximal to the retention member, cutting the sutures does not significantly move the suture lock and / or the sutures located between the suture lock and the valve leaflet.

[0304] In other embodiments, the retention member and suture lock are integrated and delivered as a unit. In some embodiments, the unit includes an anchor or is coupled to an anchor during the delivery process. The physician can adjust the length of the suture that extends between the suture lock and the valve leaflet and can use the suture lock to permanently lock the suture in place.

[0305] The resulting artificial chordae in the above examples are more durable than conventional artificial chordae. First, movement of the suture relative to the suture lock is reduced or eliminated, reducing suture wear. Second, movement of the suture lock relative to the anchor is reduced or eliminated, further reducing suture wear. Additionally, the orientation of the suture relative to the suture lock also reduces suture wear. The additional features described above (e.g., including the nose of the suture lock) increase the lifespan of the artificial chordae.

[0306] Figure 66 illustrates an anchor, retention member, and suture lock according to one embodiment of the present disclosure. Figure 67 illustrates the orientation of an artificial chordae according to an embodiment of the present disclosure.

[0307] Suture Lock Boot: In certain aspects of the present disclosure, once the tension and length of the neochordae implant is optimized, the suture lock is locked to fix the length of the suture so that the sutures no longer move relative to the suture lock.

[0308] In a further aspect of the present disclosure, to correct or minimize damage to the mitral valve, the physician applies tension to the sutures and then clamps or pins the sutures or engages and locks them in a suture lock so that the applied suture tension and length adjustment are maintained. This step and the resulting lock engagement can correct or minimize damage to the mitral valve and remain corrected for the functional lifespan of the neochordae (i.e., prosthetic chordae). To advance the suture lock through the delivery catheter and clamp or pin the sutures within the suture lock, the suture lock can be coupled to a lock driver mechanism, such as a lock screw driver in one alternative, e.g., a stored energy mechanism, that can provide the force necessary to clamp or pin the sutures within the suture lock, depending on the tightening requirements of the suture lock.

[0309] In some aspects, the suture lock may be further coupled to a boot located on or disposed with the lock driver. The boot comprises a retention mechanism configured to reversibly retain the suture lock to the boot to strengthen engagement of the lock driver. According to some embodiments, for example as shown in FIG. 68 , a system includes a delivery catheter 6905, a suture lock 6935, and a boot 6915. As shown in FIG. 68 , the suture lock 6935 has a screw 6925 that engages with a lock driver 6910. The lock driver can be rotated to advance or retract a ramp (or push wedge) 6930, which clamps (secures) the suture 6945 against the inner surface of the suture lock 6940. The suture lock 6935 is coupled to the boot 6915. The lock driver 6910 (shown in phantom) engages with the head of the screw 6925. By inserting the lock driver 6910 coaxially through the boot 6915, the suture lock retaining members 6920 (two suture lock retaining members 6920 are shown on either side of the boot 6915 in FIG. 68 ) can be forced to protrude from the outer surface of the boot 6915. The suture lock retaining members 6920 provide a friction fit (not shown) to the suture lock 6935 or engage one or more recesses (shown in dotted perspective view) in the suture lock 6935. In alternative embodiments, a friction fit between the lock driver and boot alone may be used, without the need for a suture lock retaining member or recesses. When the lock driver 6910 is positioned distal to the suture lock retaining members 6920, the suture lock retaining members 6920 of the boot 6915 couple with the suture lock 6935 to limit or eliminate movement of the suture lock 6935 relative to the boot 6915. Once the physician has tensioned the suture to correct mitral valve movement, the physician then rotates the lock driver 6910 to clamp or pin the suture within the suture lock 6935. Those skilled in the art will appreciate that alternative suture lock clamp or locking configurations, such as pushing or pulling multiple components together to engage the lock of the suture lock, are within the scope of the present disclosure.

[0310] Once the sutures are clamped within the suture lock, the physician uses any known visualization technique to confirm that the mitral valve damage or defect has been corrected or minimized. For example, if further adjustments need to be made, the physician rotates the lock driver 6910 to relieve the force on the suture 6945, adjusts the tension as needed, and repeats the procedure to clamp the suture. Once the physician is satisfied that the mitral valve damage has been corrected or minimized, the physician retracts the lock driver 6910, which clears the head of the screw 6925.

[0311] 69 and 70 illustrate the removal of the lock driver 6910 and boot 6915 from the suture lock 6935. As the lock driver 6910 retracts from the suture lock and past the suture lock retaining member, the suture lock retaining member retracts from the boot, thereby disengaging the boot 6915 from the suture lock. As the suture lock retaining member retracts, the boot 6915 disengages from the suture lock. Once the boot 6915 disengages the suture lock retaining member 6920 (not shown) from the suture lock 6935, the physician can remove the lock driver 6910 and boot 6915 from the catheter.

[0312] In some embodiments, the anchor may further include a retention member configured to mate with the suture lock such that the suture lock maintains its alignment with the anchor. In these embodiments, a physician can apply pressure to the lock driver and boot to insert the suture lock into the retention member. Once the suture lock is inserted into the retention member and the appropriate tension is applied to the suture, the suture can be clamped to the suture lock, and the lock driver and boot can be retracted from the suture lock and catheter as described above.

[0313] The suture lock further includes an alternative mechanism configured to actuate the suture retention mechanism. In some embodiments, the suture retention mechanism is a screw that can be rotated to reversibly apply and remove pressure on the suture. FIGS. 68-70 illustrate an embodiment in which the suture retention mechanism includes a screw 6925, one or more ramps 6930, and a face of the suture lock 6940. The ramp and / or opposing face of the suture lock include multiple notches. Each notch has a height that advances to clamp (secure) the suture with rotation of the screw. The height of each notch may increase or decrease from the innermost notch to the outermost notch. Other suture retention mechanisms, such as a spring or other stored energy mechanism, may also be used to provide a force to clamp the suture within the suture lock. For example, the spring can be actuated in any known manner, thereby releasing the stored energy of the spring upon removal of the boot from the suture lock.

[0314] In certain configurations, a suture may comprise a thread, cable, wire, filament, strand, line, yarn, gut, or similar structure, whether natural and / or synthetic, in monofilament, composite filament, or multifilament form (braided, woven, twisted, or otherwise held together).

[0315] While this disclosure describes specific embodiments and examples, various aspects of the systems and methods described above may be combined differently and / or modified to form further alternative or acceptable embodiments. All such modifications and variations are included within the scope of this disclosure. Indeed, a wide variety of designs and approaches are possible and are included within the scope of this disclosure.

[0316] Furthermore, certain features that are described in this disclosure in the context of separate embodiments may also be implemented in combination in a single embodiment. Alternatively, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable combination. Furthermore, although features may be described as operating in a particular combination, one or more features of a claimed combination may be independent of the combination, as appropriate, and a combination may be claimed as a subcombination or a variation of the subcombination.

[0317] Any particular feature, aspect, method, property, quality, attribute, element, etc. disclosed herein in connection with various embodiments can be used in all other embodiments described herein, and any method described herein may be performed using any apparatus suitable for performing the recited steps.

[0318] Furthermore, while components and operations may be illustrated or described in a particular arrangement or order, such components and operations need not be arranged or performed in the particular arrangement and order illustrated or described to achieve desirable results, nor need all components and operations be included. Other components and operations not illustrated or described may be incorporated into the embodiments and examples. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the described operations. Furthermore, operations may be reordered or rearranged in other embodiments. Also, the separation of various system components in the above embodiments should not be understood as requiring such separation in all embodiments; the described components and systems may generally be integrated into a single product or packaged into multiple products.

[0319] That is, various illustrative embodiments and examples are described herein. While the systems and methods are disclosed in connection with the above embodiments and examples, the disclosure extends to other alternative embodiments and / or other uses of the embodiments, as well as modifications and equivalents, other than the specifically disclosed embodiments. The disclosure expressly contemplates that various features and aspects of the disclosed embodiments may be combined with or substituted for one another. Therefore, the scope of the disclosure should not be limited to the particular embodiments disclosed, but should be determined solely by a fair reading of the following claims and the full scope of their equivalents. According to aspect (1), Hub and a suture extending proximally from the hub; a helical anchor extending distally from the hub; a second anchor axially movable distally from a first configuration to a deployed second configuration to engage tissue and prevent disengagement of the helical anchor; The tissue anchor comprises: According to aspect (2), the second anchor is characterized by having a branch extending between a proximal end and a pointed distal end. According to aspect (3), the branch portion is supported by a support portion. According to aspect (4), the support portion has a ring structure. According to aspect (5), the support receives a tubular structure of a deployment system for advancing the support distally relative to the helical anchor. According to aspect (6), the hub has a branch guide that is movable in the axial direction and receives the branch. According to aspect (7), the branch guide has a deflection surface for deflecting the branch at a launch angle inclined radially outward in the distal direction. According to aspect (8), the emission angle is in the range of approximately 30° to 45°. According to aspect (9), the hub has an axially movable opening that receives the second anchor. According to aspect (10), the device further comprises a core wire attached to the hub and extending concentrically through the spiral anchor. According to aspect (11), the device further comprises a suture anchor guide extending proximally from the hub. According to aspect (12), in the deployed second configuration, the second anchor extends through the suture anchor guide. According to aspect (13), the second anchor extends through an opening in the suture anchor guide. According to aspect (14), when the second anchor moves to the deployed second configuration, the second anchor is operable to penetrate the suture anchor guide. According to aspect (15), the device further comprises a radiopaque marker supported by the second anchor. According to aspect (16), the device further comprises a core wire attached to the hub and extending concentrically through the spiral anchor. According to aspect (17), the device further comprises a radiopaque marker supported by the core wire so as to be axially movable. According to aspect (18), the device further comprises a spring supported by the core wire. According to aspect (19), the core wire extends distally beyond the helical anchor. According to aspect (20), the catheter further comprises a distal stopper provided on the core wire operable to limit the movement of the radiopaque marker in the distal direction. According to aspect (21), the helical anchor further includes a tissue penetration point at a distal end of the helical anchor, and a folded portion provided on the helical anchor, located proximal to the point, and configured to resist rotation of the helical anchor out of engagement with tissue. According to aspect (22), the second anchor is operable to increase the anchor torque resistance of the tissue anchor by 2 to 5 times compared to the anchor torque resistance of the tissue without the second anchor. According to aspect (23), the anchor torque resistance of the spiral anchor having the second anchor is 2N / cm to 5 / Ncm. According to aspect (24), the second anchor is operable to increase the anchor torque resistance of the tissue anchor by at least two times compared to the anchor torque resistance of the tissue anchor without the second anchor. According to aspect (25), the anchor torque resistance of the spiral anchor is greater than 2 N / cm. According to aspect (26), there is provided a method for implanting a transvascular artificial chordae, comprising: advancing a catheter into the left atrium and through the mitral valve into the left ventricle; deploying a ventricular anchor from the catheter to the wall of the left ventricle by rotating a helical tissue anchor into the wall of the left ventricle; deploying a second tissue anchor in the wall of the left ventricle to inhibit dislodgment of the helical tissue anchor; maintaining the ventricular suture attached to the ventricular anchor and extending proximally through the catheter; Fixing a valve leaflet anchor catheter to the mitral valve leaflet from the atrial side; With the leaflet anchor catheter secured to the leaflet, advancing a leaflet anchor from the catheter through the mitral valve leaflet to secure the mitral valve leaflet to a leaflet suture, the leaflet suture extending proximally through the catheter; securing the leaflet sutures to the ventricular sutures to limit the extent of movement of the leaflets toward the left atrium; The method is characterized by comprising: According to aspect (27), the step of deploying the second tissue anchor includes a step of axially advancing the second tissue anchor distally relative to the spiral tissue anchor. According to aspect (28), the step of deploying the second tissue anchor is characterized by increasing the anchor torque resistance of the ventricular anchor by 2 to 5 times compared to the anchor torque resistance of the ventricular anchor without the second anchor. According to aspect (29), the anchor torque resistance of the tissue anchor and the second tissue anchor is between 2 N / cm and 5 N / cm. According to aspect (30), the second tissue anchor increases the anchor torque resistance of the ventricular anchor by at least two times compared to the anchor torque resistance of the ventricular anchor without the second anchor. According to aspect (31), the anchor torque resistance between the second tissue anchor and the ventricular anchor is at least greater than 2 N / cm. According to aspect (32), there is provided an access system for directing a ventricular ancas sheath to a target site in a left ventricle, the access system comprising: a delivery catheter having an elongated flexible tubular body having a proximal end, a distal end, a central axis, and a steering zone near the distal end, the steering zone being actively deflectable to provide a delivery catheter curve that lies within a delivery catheter curve plane; an anchor sheath axially advanceable through the delivery catheter, the anchor sheath having a proximal preset curve and a distal preset curve that lie in a proximal preset curve plane; The anchor sheath is configured to rotate within the delivery catheter to bias the proximal preset curve surface into alignment with the delivery catheter curve surface in response to axial alignment of the proximal preset curve within the delivery catheter curve. According to aspect (33), the distal preset curve lies in a distal preset curve plane that is angled from the proximal preset curve plane. According to aspect (34), the delivery catheter curve is actively adjustable over a range of at least 10° to 150°. According to aspect (35), there is provided an access system for directing a ventricular ancasheat to a target site in a left ventricle, the access system comprising: a delivery catheter having an elongated flexible tubular body having a proximal end, a distal end, and a steering zone near the distal end, the steering zone being actively deflectable to provide a delivery catheter curve that lies within a delivery catheter curve plane; an anchor sheath axially advanceable through the delivery catheter, the anchor sheath having a proximal preset curve and a distal preset curve that lie in a proximal preset curve plane; The proximal preset curve and the delivery catheter curve are configured to cooperate to provide a tactile indication of rotational alignment of the anchor sheath within the delivery catheter, the access system. According to aspect (36), there is provided a ventricular anchor delivery sheath, comprising: an elongated flexible tubular body having a proximal end, a distal end, and a longitudinal axis; a proximal preset curve of the tubular body; a distal preset curve of the tubular body. According to aspect (37), the proximal preset curve lies in a first plane and the distal preset curve lies in a second plane, the second plane being rotationally angled from the first plane. According to aspect (38), the second plane is rotationally angled from the first plane at an angle in the range of 40° to 75°. According to aspect (39), the distal preset curve has an angle in the range of 5° to 60° in the first plane. According to aspect (40), the length of the distal preset curve is 50% or less of the length of the proximal preset curve. According to aspect (41), the length of the distal preset curve is 20% or less of the length of the proximal preset curve. According to aspect (42), the distance between the longitudinal center of the proximal preset curve and the longitudinal center of the distal preset curve ranges between 45 and 85 millimeters. According to aspect (43), the longitudinal center of the distal preset curve is within a range of 50 to 70 millimeters from the distal end of the ventricular anchor delivery sheath. According to aspect (44), the longitudinal center of the proximal preset curve is within a range of 100 to 145 millimeters from the distal end of the ventricular anchor delivery sheath. According to aspect (45), the device further comprises a distal anchor section having a foldable sidewall. According to aspect (46), there is provided a ventricular anchor delivery sheath, comprising: an elongate flexible tubular body having a proximal end, a distal end, and a longitudinal axis; a distal preset curve of the tubular body. According to aspect (47), the longitudinal center of the distal preset curve is within a range of 50 to 70 millimeters from the distal end of the ventricular anchor delivery sheath.

Claims

1. Hub and a suture extending proximally from the hub; a helical anchor extending distally from the hub; a second anchor axially movable distally from a first configuration to a deployed second configuration to engage tissue and prevent disengagement of the helical anchor; A tissue anchor comprising:

2. 10. The tissue anchor of claim 1, wherein the second anchor has prongs extending between a proximal end and a pointed distal end.

3. The tissue anchor according to claim 2 , wherein the prongs are supported by a support.

4. The tissue anchor of claim 3 , wherein the support portion has an annular structure.

5. 5. The tissue anchor of claim 3 or 4, wherein the support portion receives a tubular structure of a deployment system for distally advancing the support portion relative to the helical anchor.

6. 3. The tissue anchor of claim 2, wherein the hub has axially movable prong guides that receive the prongs.

7. 7. The tissue anchor of claim 6, wherein the prong guides have deflection surfaces for deflecting the prongs at a launch angle that is angled radially outward in a distal direction.

8. 8. The tissue anchor of claim 7, wherein the firing angle is in the range of approximately 30 degrees to 45 degrees.

9. The tissue anchor of claim 1 , wherein the hub has an axially movable opening that receives the second anchor.

10. 10. The tissue anchor of claim 1, further comprising a core wire attached to the hub and extending concentrically through the helical anchor.

11. The tissue anchor of any preceding claim, further comprising a suture anchor guide extending proximally from the hub.

12. 12. The tissue anchor of claim 11, wherein in a deployed second configuration, the second anchor extends through the suture anchor guide.

13. 13. The tissue anchor of claim 12, wherein the second anchor extends through an opening in the suture anchor guide.

14. 14. The tissue anchor of claim 13, wherein the second anchor is operable to pass through the suture anchor guide when the second anchor is moved to the deployed second configuration.

15. The tissue anchor of claim 1 further comprising a radiopaque marker carried by the second anchor.

16. 16. The tissue anchor of any preceding claim, further comprising a core wire attached to the hub and extending concentrically through the helical anchor.

17. 17. The tissue anchor of claim 16, further comprising a radiopaque marker axially movably supported by the core wire.

18. 17. The tissue anchor of claim 16, further comprising a spring supported on the core wire.

19. 17. The tissue anchor of claim 16, wherein the core wire extends distally beyond the helical anchor.

20. 17. The tissue anchor of claim 16, further comprising a distal stop on the core wire operable to limit distal movement of the radiopaque marker.

21. 10. The tissue anchor of claim 1, further comprising: a tissue penetration point at a distal end of the helical anchor; and a turn-up portion on the helical anchor located proximal to the point and configured to resist rotation of the helical anchor out of engagement with tissue.

22. 22. The tissue anchor of any preceding claim, wherein the second anchor is operable to increase the anchor torque resistance of the tissue anchor by a factor of 2 to 5 compared to the anchor torque resistance of the tissue without the second anchor.

23. 22. The tissue anchor according to any one of claims 1 to 21, wherein the anchor torque resistance of the helical anchor having the second anchor is 2 N / cm to 5 N / cm.

24. 22. The tissue anchor of any preceding claim, wherein the second anchor is operable to increase the anchor torque resistance of the tissue anchor by at least a factor of two compared to the anchor torque resistance of the tissue anchor without the second anchor.

25. 22. The tissue anchor according to any one of claims 1 to 21, wherein the anchor torque resistance of the helical anchor is greater than 2 N / cm.

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