Heart treatment system

Abstract

Disclosed are systems and methods of removing heart valve therapy. The systems and methods may include chordae cutting devices having unique shape memory curvature, capture basket catheters with mesh baskets, and leaflet cutting tools with unique shapes that may be pulled through leaflet tissue.

Description

HEART TREATMENT SYSTEMRELATED APPLICATIONS

[0001] This application claims benefit of and priority to U.S. Provisional Application Serial No. 63 / 557,356 filed February 23, 2024 entitled Leaflet Cutter With A Snare, and to U.S. Provisional Application Serial No. 63 / 671 ,685 entitled Chord Cutter and Basket Improvements, both of which are hereby incorporated herein by reference in their entireties.BACKGROUND

[0002] Heart valve conditions can occur when the leaflets of a patient’s valve are unable to fully close, which allows blood to regurgitate or abnormally flow backward. Regurgitation is especially common with the mitral valve in which the mitral valve anterior leaflet fails to properly coapt with the posterior leaflet. As the ventricles of the heart contract, some blood moves from the left ventricle, back into the left atrium instead of into the aorta. Similar regurgitation may also occur with the tricuspid valve, allowing blood to flow from the right ventricle back into the right atrium.

[0003] A common treatment for valvular regurgitation is the use of treatment devices that appose or permanently connect the leaflets together. This heart valve therapy hardware may have been placed using surgical, transcatheter, or minimally-invasive means. For example, the hardware or therapy targeted for removal may be the MitraClip (Abbott Structural, Santa Clara, CA), the PASCAL device (Edwards Lifesciences, Irvine, CA), a suture placed surgically (e.g., Alfieri stitch), or similar heart valve therapy. Other heart valve therapy may be the result of techniques that have involved leaflets as part of a therapeutic target, and the part or whole leaflet involvement requires removal. Other examples include chordal replacement technologies placed with either transcatheter methods or surgery to compensate for improper length, disruption, or mispositioning of existing chords. For purposes of the present application, the phrase “heart valve therapy” shall be defined as any devices and / or methods used for therapeutic treatment of a heartvalve, such as leaflet clips, sutures, artificial chords, or any other devices or methods associated with the treatment of heart valves and associated leaflets.

[0004] These heart valve therapies are typically removed via open heart surgery, which can be particularly traumatic for patients and presents a relatively high risk of complications. Therefore, there is an ever-present need for less traumatic approaches to removing heart valve therapy that presents a lower risk of complications.SUMMARY

[0005] In some aspects, the techniques described herein relate to a tissue cutting catheter for use within a heart, including: an elongated control member; wire connected to a distal portion of the elongated control member; wherein the wire has a memorized unconstrained shape forming a first curve; and, one or more electrodes positioned at an apex of the first curve.

[0006] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve includes a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein the second wire segment and the fourth wire segment form an angle within an inclusive range of about 30 and about 50 degrees.

[0007] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve includes a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein the second wire segment and the fourth wire segment form an angle within an inclusive range of about 35 and about 45 degrees.

[0008] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve includes a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein a circle tangentially contacting the second wire segment, the third wire segment, and the fourth wire segment has a diameter within an inclusive range of about 2.5 mm to about 13 mm.

[0009] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve includes a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein a circle tangentially contacting the second wire segment, the third wire segment, and the fourth wire segment has a diameter within an inclusive range of about 3.7 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, or 4.4 mm.

[0010] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve includes a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein the first wire segment, the second wire segment, the third wire segment, and the fourth wire segment are positioned at different angles relative to each other.

[0011] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first wire segment, the second wire segment, the third wire segment, and the fourth wire segment are positioned substantially within a same plane.

[0012] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the second wire segment, the third wire segment, and the fourth wire segment are substantially positioned within a first plane and wherein the first wiresegment is substantially positioned within a second plane that is different than the first plane.

[0013] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve is formed by the second wire segment, the third wire segment, and the fourth wire segment, and wherein the first curve curves in a substantially clockwise direction when viewed towards a distal direction.

[0014] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve is formed by the second wire segment, the third wire segment, and the fourth wire segment, and wherein the first curve curves in a substantially clockwise direction when viewed towards a distal direction.

[0015] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the first curve is formed by the second wire segment, the third wire segment, and the fourth wire segment, and wherein the first curve curves in a substantially counter-clockwise direction when viewed towards a distal direction.

[0016] In some aspects, the techniques described herein relate to a tissue cutting catheter, wherein the wire is formed into a loop and wherein the loop forms the first wire segment, the second wire segment, the third wire segment, and the fourth wire segment.

[0017] In some aspects, the techniques described herein relate to a capture basket catheter for use within a heart, including: an elongated catheter body; a mesh basket formed of one or more wires braided together and connected at a distal portion of the elongated catheter body; and, at least one flexible filament connected at a plurality of locations on the mesh basket so as to limit sizes of cells of the mesh basket.

[0018] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the one or more wires braided together form a plurality of crossing wire segments; and wherein the at least one flexible filament forms a knot or loop around at least some of the crossing wire segments.

[0019] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the at least one flexible filament forms a circumferential pattern around the mesh basket.

[0020] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the at least one flexible filament also extends longitudinally along the mesh basket.

[0021] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the at least one flexible filament extends along a distal quarter, a distal third, or distal half of the mesh basket.

[0022] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the at least one flexible filament includes a stretch resistant material or an elastic material.

[0023] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the at least one flexible filament includes a solid PET filament, a solid metal filament, a plurality of polymer yarn fibers, or a solid silicone filament.

[0024] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the mesh basket includes an opening into a cavity of the basket that opens in a proximal direction when in an expanded configuration.

[0025] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the elongated catheter body further includes a distal tip member including a retaining portion connected to a crossing point of two wire segments of the one or more wires.

[0026] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the retaining portion includes two upper mesh wire openings and two lower mesh wire openings; and wherein the two wire segments each pass through one of the two upper mesh wire openings and one of the two lower mesh wire openings.

[0027] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the distal tip member further includes two cinch wire openings and wherein a cinch wire is positioned through the two cinch wire openings and through loops of the mesh basket.

[0028] In some aspects, the techniques described herein relate to a capture basket catheter for use within a heart, including: an elongated catheter body having; a mesh basket formed of one or more wires braided together; and, a distal tip member including a retaining portion connected to a crossing point of two wire segments of the one or more wires.

[0029] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the retaining portion includes two upper mesh wire openings and two lower mesh wire openings; and wherein the two wire segments each pass through one of the two upper mesh wire openings and one of the two lower mesh wire openings.

[0030] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the distal tip member further includes two cinch wire openings and wherein a cinch wire is positioned through the two cinch wire openings and through loops of the mesh basket.

[0031] In some aspects, the techniques described herein relate to a capture basket catheter, wherein the two upper mesh wire openings and the two lower mesh wire openings are located distally of the two cinch wire openings.

[0032] In some aspects, the techniques described herein relate to a tissue cutting device for use within a heart, including: an elongated catheter body; a core wire connected to a distal end of the elongated catheter body; the core wire including a memorized shape when unconstrained that forms a first curve, a snare attachment structure at or near a distal tip of the core wire, and one or more electrodes positioned along the first curve.

[0033] In some aspects, the techniques described herein relate to a tissue cutting device, wherein the first curve is within an inclusive range of about 160 to about 200 degrees.

[0034] In some aspects, the techniques described herein relate to a tissue cutting device, wherein the snare attachment structure is a second curve of the core wire, a sleeve, a coil, or a weld mass.

[0035] In some aspects, the techniques described herein relate to a tissue cutting device, further including a radiopaque marker positioned on a proximal segment of the core wire at a location laterally even with the snare attachment structure.

[0036] In some aspects, the techniques described herein relate to a tissue cutting device, further including a leaflet puncture tool positioned over the elongated catheter body and the core wire.

[0037] In some aspects, the techniques described herein relate to a method of removing a heart valve therapy device; including: positioning a core wire of a tissue cutting catheter from a first side of a valve through to a second side of the valve; looping a first curve of the core wire around the heart valve therapy device on the second side of the valve; positioning a snare attachment structure on a distal region of the core wire back through to the first side of the valve; engaging a snare catheter with the snare attachment structure; and, activating one or more electrodes along the first curve of the core wire to separate the heart valve therapy device from leaflets of the valve.

[0038] In some aspects, the techniques described herein relate to a method of modifying a heart leaflet; including: puncturing a heart leaflet with a leaflet puncture tool to create a first opening; positioning a core wire of leaflet cutting catheter from a first side of a valve through to a second side of the heart valve; positioning a snare loop of a snare catheter through a second opening of the heart valve to the second side of the heart valve; engaging the snare loop with a snare attachment structure of a distal region of the core wire; and, activating one or more electrodes along the core wire while pulling the leaflet cutting catheter and the snare catheter to cut the heart leaflet.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The following figures are included to illustrate certain example aspects of the present disclosure and should not be viewed as exclusive or limiting. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to one having ordinary skill in the art and having the benefit of this disclosure. The present disclosure references the drawings as follows:

[0040] Fig. 1 illustrates a distal end of a tissue cutting catheter having a wire in its unconstrained configuration forming a curve (e.g., a hook or "J" shape).

[0041] Fig. 2 illustrates a distal end of a snare catheter having a wire loop that forms a generally saddle-shape when unconstrained.

[0042] Fig. 3 illustrates a distal end of a cutting element catheter, having a wire with a plurality of electrodes.

[0043] Fig. 4 illustrates a distal end of a capture basket catheter, having a basket with a proximally facing opening.

[0044] Figs. 5, 6, 7, and 8 illustrate an example procedure with the catheters shown in Figs. 1 -4 for removing a valve leaflet clip that is attached to mitral valve leaflets of a mitral valve or alternatively to a tricuspid valve.

[0045] Fig. 9 illustrates a perspective view of a distal end of a tissue cutting catheter.

[0046] Fig. 10 illustrates a side view of the tissue cutting catheter.

[0047] Fig. 11 illustrates a side view of the tissue cutting catheter.

[0048] Fig. 12 illustrates a side view of the tissue cutting catheter.

[0049] Fig. 13 illustrates an end view of the tissue cutting catheter looking distally.

[0050] Fig. 14 illustrates an end view of the tissue cutting catheter looking proximally.

[0051] Fig. 15 illustrates a perspective view of a distal end of the tissue cutting catheter.

[0052] Fig. 16 illustrates another perspective view of the tissue cutting catheter.

[0053] Fig. 17 illustrates a side view of the tissue cutting catheter.

[0054] Fig. 18 illustrates another side view of the tissue cutting catheter.

[0055] Fig. 19 illustrates an end view of the tissue cutting catheter looking in a distal direction.

[0056] Fig. 20 illustrates an end view of the tissue cutting catheter looking in a proximal direction.

[0057] Fig. 21 illustrates a perspective view of a distal end of the tissue cutting catheter.

[0058] Fig. 22 illustrates another perspective view of the tissue cutting catheter.

[0059] Fig. 23 illustrates a side view of the tissue cutting catheter.

[0060] Fig. 24 illustrates another side view of the tissue cutting catheter.

[0061] Fig. 25 illustrates an end view of the tissue cutting catheter looking in a distal direction.

[0062] Fig. 26 illustrates an end view of the tissue cutting catheter looking in a proximal direction.

[0063] Fig. 27 illustrates a side view of a capture basket catheter 130 that includes flexible filament 136 along a distal portion of a mesh basket 131 .

[0064] Fig. 28 illustrates an enlarged view of the mesh basket of Fig. 27.

[0065] Fig. 29 illustrates a side view of the capture basket catheter in use with a snare catheter and a captured valve leaflet clip.

[0066] Fig. 30 illustrates the valve leaflet clip positioned within the mesh basket of the capture basket catheter.

[0067] Fig. 31 illustrates the proximal opening of the mesh basket cinched closed by the cinch wire around the snare catheter.

[0068] Fig. 32 illustrates a side view of the distal tip member.

[0069] Fig. 33 illustrates another side view of the distal tip member at about 90 degrees to the view of Fig. 32.

[0070] Fig. 34 illustrates a side view of a tissue cutting device that may be used for cutting a tissue bridge connecting a heart valve therapy device (e.g., valve leaflet clip).

[0071] Fig. 35 illustrates a side view of the tissue cutting device from a different side view that is about 90 degrees from the view of Fig. 34.

[0072] Fig. 36 illustrates a perspective view of the tissue cutting device.

[0073] Fig. 37 illustrates a view of mitral valve leaflets of a mitral valve within a left ventricle.

[0074] Fig. 38 illustrates a view of mitral valve leaflets of a mitral valve within a left ventricle.

[0075] Fig. 39 illustrates a view of mitral valve leaflets of a mitral valve within a left ventricle.

[0076] Figs. 40 and 41 illustrate views of the valve leaflet clip on the mitral valve leaflets.

[0077] Fig. 42 illustrates a view of the mitral valve leaflets from the left atrium side.

[0078] Fig. 43 illustrates a view of the mitral valve leaflets from the left atrium side.

[0079] Fig. 44 illustrates a view of the mitral valve leaflets from the left atrium side.

[0080] Fig. 45 illustrates a view of the mitral valve leaflets 14 from the left atrium 10 side.

[0081] Fig. 46 illustrates a side view of a leaflet cutting system that may comprise a leaflet cutting catheter, a leaflet puncture tool, and a snare catheter.

[0082] Fig. 47 illustrates a left ventricle side of mitral valve leaflets.

[0083] Fig. 48 illustrates another view of the left ventricle side of the mitral valve leaflets.

[0084] Fig. 49 illustrates another view of the left ventricle side of the mitral valve leaflets.

[0085] Fig. 50 illustrates another view of the left ventricle side of the mitral valve leaflets.DETAILED DESCRIPTION

[0086] It will be appreciated by persons skilled in the art that the present disclosure is not limited to what has been particularly shown and described herein. A variety of modifications and variations are possible in view of the teachings herein without departing their scope, spirit, or intent.

[0087] While different examples may be described in this specification, it is specifically contemplated that any of the features from the different examples can be used and brought together in any combination. In other words, the features of different examples can be mixed and matched with each other. Hence, while every permutation of features from different examples may not be explicitly shown or described, it is the intention of this disclosure to cover any such combinations, especially as may be appreciated by one of skill in the art.

[0088] The terminology used in this disclosure should be interpreted in a permissive manner and is not intended to be limiting. In the drawings, like numbers refer to like elements. Unless otherwise noted, all of the accompanying drawings are not to scale. Unless otherwise noted, the term “about” is defined to mean plus-or-minus 5% of a stated value.

[0089] The terms distal or distally generally refer to a direction or area towards an end of a device within a patient (e.g., away from a physician / clinician), while the terms proximal or proximally refer to a direction or area toward an end of a device that remains outside of a patient (e.g., toward or closer to a physician / clinician or handle / hub of a device).

[0090] Numerical ranges discussed in this specification should be interpreted as both inclusive numerical ranges and as covering / disclosing a plurality of numbers within the ranges. Specifically, a range should be considered to recite numbers that increment by two decimal places (hundredths) for the purposes of support in the claims (e.g., 0.01 , 0.02, 0.03, etc.). Any of these incremented numbers from a range should be understood to have significance and importance in the context of the present specification.

[0091] While the examples of this specification may be specifically described with regard to a mitral valve, they may also be used in connection with other valves, such as a tricuspid valve.

[0092] Figures 1 -3 illustrate the distal ends of various catheter tools that may be used to treat a cardiac valve, including removing certain heart valve therapy device (e.g., a heart leaflet clip). These catheter tools, and an example use with a steerable sheath 116 are described in Figs. 4-8.

[0093] Fig. 1 illustrates a distal end of a tissue cutting catheter 184 having a wire 184A in its unconstrained configuration forming a curve 184D (e.g., a hook or “J” shape or “V” shape). Optionally, the wire 184A may also be formed into a loop shape, as seen in Fig. 1 , but may alternatively take the form of a non-looped curved wire.

[0094] A plurality (e.g., two) electrodes 184B may be located on the wire 184A. In some examples, the electrodes 184B are located at least at the base / apex of the curve 184D (or “V” shape), and optionally at other locations. In some examples, the curve or “V” shape may help funnel chordae or tissue to the location of electrodes 184B. In some examples, the wire 184A may be conductive and have shape memory properties (e.g., Nitinol), the wire 184A may have an insulative layer along most of its length, and the electrodes 184B may comprise a more heat resilient material (e.g., stainless steel) connected over and directly to the shape memory material. Hence, the curve 184D may be shape set with the shape memory material and the electrodes 184B may desirably conduct electrical current with minimal or no damage.

[0095] The wire 184A may be connected to an elongated catheter body 184C that includes a conductive pathway in communication with the wire 184A and a proximal end of the elongated catheter body 184C, allowing it to be connected to a current source (e.g., monopolar radiofrequency current). Hence, the length of the elongated catheter body 184C is sufficient to reach a desired target location within a heart from outside a patient’s body. The electrodes 184B of the wire 184A may further conduct the current which, when in proximity or contact with tissue, may cut the tissue. This tool may be particularly useful for cutting chordae and tissue (e.g., leaflet tissue) within a heart.

[0096] Fig. 2 illustrates a distal end distal end of a snare catheter 186 having a wire loop 186A that forms a generally saddle-shape when unconstrained. The wire loop 186A may be attached to an elongated control wire within a catheter body 186C of the snare catheter 186 that extends down to a proximal end of the catheter body 186C, allowing a user to pull the control wire and therefore the wire loop 186A into one or more openings 186B at a distal portion of the catheter body 186C of the snare catheter 186. The control wire and catheter body 186C may have a length that allows the wire loop 186A to be advance within the heart of a patient while being proximally accessed by a physician. Hence, the wire loop 186A may be closed around an object during a procedure, especially within a heart. This tool may be particularly useful for snaring a heart valve therapy device, such as a leaflet clip, during a heart valve therapy removal procedure.

[0097] Fig. 3 illustrates a distal end of a cutting element catheter 188, having a wire 188A with a plurality of electrodes 188B. The wire 188A may be in the form of a loop (e.g., a curved or saddle-shaped loop) attached to an elongated catheter body 188C that conducts electrical current (e.g., monopolar radiofrequency current) from its proximal end to the wire 188A and plurality of electrodes 188B when near or in contact with tissue. In some examples, the wire 188A may be composed of a shape memory wire with an electrical insulation layer around its outside. Each of the plurality of electrodes 188B may optionally be composed of a non-shape memory material (e.g., stainless steel) that is more resilient to heat damage. The wire 188A may form a generally saddle shape when unconstrained so that when it is pulled into a larger sheath or catheter, a distal end of the wire 188A closes around a desired target device. This tool may be particularly useful for moving around a heart valve therapy device, such as a leaflet clip, and then cutting leaflet tissue adjacent to the heart valve therapy device, thereby freeing the heart valve therapy device.

[0098] Fig. 4 illustrates a distal end of a capture basket catheter 190, having a basket 190A with a proximally facing opening. The basket 190A may be composed of a mesh or similar material that is attached to a cinch loop 190B. In some examples, the mesh may be composed of either a single Nitinol wire braided amongst itself or a plurality of braided Nitinol wires. The cinch loop 190B may be attached to an elongated control wire within a catheter body 190C that extends down to a proximal end of the catheter body 190C, allowing a user to pull the control wire at a proximal location and thereby also pull the cinch loop 190B, cinching or closing the opening of the basket 190A. In some examples, the basket 190A and / or the cinch loop 190B may include a layer of electrical insulation to prevent unwanted electrical conduction when used with a cutting element catheter 188. This tool may be particularly useful for capturing a heart valve therapy device, such as a leaflet clip, that has been removed from valve leaflets.

[0099] Figs. 5-8 illustrate an example procedure with the catheters shown in Figs. 1-4 for removing a valve leaflet clip 50 that is attached to mitral valve leaflets 14 of a mitral valve.

[0100] Turning to Fig. 5, initially a left atrium 10 of a heart is accessed via a transeptal procedure. A distal end of a steerable sheath 116 is then advanced across the septum of the heart and into the left atrium above the mitral valve leaflets 14. In some examples, a further catheter or sheath 109 may be advanced out of the steerable sheath 116, through the mitral valve leaflets 14, and into the left ventricle 12. The tissue cutting catheter 184 may be advanced through the sheath 109 such that its wire 184A is also positioned in the left ventricle 12 of the heart, below the mitral valve leaflets 14. The tissue cutting catheter 184 may be activated (e.g., RF current applied) to help cut the chordae 15 and other tissue that may surround or be attached to the valve leaflet clip 50, thereby allowing the valve leaflet clip 50 to be better accessed. Additionally, other tissue, such as the mitral valve leaflets 14 may also be cut as necessary.

[0101] Turning to Fig. 6, the tissue cutting catheter 184 may be withdrawn back into the sheath 109 and / or steerable sheath 116 (and / or completely removed from the system) and the snare catheter 186 and cutting element catheter 188 may be advanced through the steerable sheath 116. The wire loop 186A of the snare catheter 186 may first be advanced between the mitral valve leaflets 14 and into the left ventricle 12 so that the wire loop 186A is positioned around and then tightened around the valve leaflet clip 50.

[0102] Turning to Fig. 7, the snare catheter 186 may be moved distally away from the mitral valve leaflets 14 to help distally move the valve leaflet clip 50 and expose the tissue of the mitral valve leaflets 14 closest to the valve leaflet clip 50. The wire 188A (e.g., wire loop) of the cutting element catheter 188 may be moved proximally and immediately above the valve leaflet clip 50, and then the plurality of electrodes 188B of the wire 188A may be activated (e.g., with RF current) to cut the tissue of the mitral valve leaflets 14 and thereby release the valve leaflet clip 50.

[0103] Turning to Fig. 8, the cutting element catheter 188 may be removed from the steerable sheath 116 and / or sheath 109 and replaced with the capture basket catheter 190. The wire loop 186A of the snare catheter 186 may proximally retract the valve leaflet clip 50 into the left atrium 10 and then the mesh basket 190A may be placed over thevalve leaflet clip 50 and at least partially cinched closed. The valve leaflet clip 50, the snare catheter 186, and the capture basket catheter 190 may be removed from the heart.

[0104] In some examples, patients may have two valve leaflet clips 50 and therefore the main passage of the steerable sheath 116 may be large enough in diameter to fully remove a first valve leaflet clip 50 and left in place to allow a new removal device(s) to be introduced to remove the second valve leaflet clip 50. The steerable sheath 116 may also be removed or left in place so that any further procedure may be performed, such as replacement of the mitral valve leaflets 14 with an artificial valve and closing the opening created through the heart septum. While a mitral valve is described, a similar procedure may be performed on any of the valves in a heart (e.g., tricuspid valve).

[0105] As previously described, the tissue cutting catheter 184 of Fig. 1 may be used for a variety of different cutting procedures within a heart, such as cutting chordae of a mitral valve. Depending on the usage and needs of a procedure, different shapes and configurations may be helpful.

[0106] One such example may be seen in Fig. 9, which illustrates a perspective view of a distal end of a tissue cutting catheter 100. Fig. 10 illustrates a side view of the tissue cutting catheter 100. Fig. 11 illustrates a side view of the tissue cutting catheter 100. Fig. 12 illustrates a side view of the tissue cutting catheter 100. Fig. 13 illustrates an end view of the tissue cutting catheter 100 looking distally. Fig. 14 illustrates an end view of the tissue cutting catheter 100 looking proximally. These figures will be discussed concurrently below.

[0107] The tissue cutting catheter 100 is generally similar to the previously described tissue cutting catheter 184 but with a wire 104 at a distal end of the tissue cutting catheter 100 which forms a unique memorized curved shape 102 when unconstrained. In some examples, the wire 104 may form a loop shape with a distal looped opening 104A and alternatively the wire 104 may form a non-looped shape, such as a single length of wire. The wire 104 may be inclusive of both traditional wires, metallic struts, and similar structural members. In some examples, the memorized curved shape 102 positions adistal tip of the wire 104 proximally of an apex of the memorized curved shape 102 and proximally of one or more electrodes 106 of the wire 104.

[0108] In some examples, the wire 104 may be composed of a shape memory wire material, such as Nitinol, that allows the memorized curved shape 102 to be imparted. The wire 104 may be connected to a distal portion of an elongated control wire 105 (Figs.13, 14) which has a length that allows the distal end of the 100 to reach a patient’s heart while a physician manipulates a proximal portion of the tissue cutting catheter 100.

[0109] The wire 104 may include one or more electrodes 106 (e.g., 1 , 2, 3, 4, 5, 6, or more electrodes). The electrodes 106 may be directly connected to the wire 104 and may be composed of a material that is resilient to electrical or heat damage. For example, the one or more electrodes 106 may be composed of stainless steel. The one or more electrodes 106 may extend completely around a diameter of the wire 104 or may only be located along a partial diameter of the wire 104, such as only on an inner surface of the memorized curved shape 102. An insulating coating may be disposed on exposed areas of the wire 104 other than the one or more electrodes 106. Electrical current, such as monopolar RF current, may be supplied to a proximal portion of the elongated control wire 105 to the wire 104, and further to the one or more electrodes 106 as needed by the physician to selectively cut cardiac tissue. In some examples, at least some of the one or more electrodes 106 are located at an apex of the memorized curved shape 102, which may be the third wire segment 102C in the present example.

[0110] In the present example, the memorized curved shape 102 curves in a way that the wire 104 is generally maintained in a single plane. In other words, with reference to a longitudinal axis 100A of the tissue cutting catheter 100 (Fig. 10), the memorized curved shape 102 curves away from the longitudinal axis 100A along only a single radial direction. Hence, the memorized curved shape 102 is generally flat, as seen in Figs. 11 -14.

[0111] In the present example, the memorized curved shape 102 may be made up of a plurality of straight segments that are angled relative to each other. Alternatively, thememorized curved shape 102 may be an entirely continuous curved shape. A first wire segment 102A may be generally aligned or parallel to the longitudinal axis 100A. A second wire segment 102B is connected to and extends from a distal end of the first wire segment 102A at an angle within a plane, a third wire segment 102C is connected to and extends from a distal end of the second wire segment 102B at an angle within the same plane, and a fourth wire segment 102D is connected to and extends from a distal end of the third wire segment 102C. Each of these segments may be positioned at different angles relative to adjacent segments but also may substantially remain within the same plane.

[0112] In some examples, the third wire segment 102C is generally perpendicular to the 100A and may include one or more electrodes 106. In some examples, a distal end of the fourth wire segment 102D is positioned further proximally than the third wire segment 102C. In some examples, a longitudinal axis for each of the second wire segment 102B and the fourth wire segment 102D form an angle 102E (Fig. 10) with each other within an inclusive range of about 0 and about 90 degrees. In some examples, a longitudinal axis for each of the second wire segment 102B and the fourth wire segment 102D form an angle 102E (Fig. 10) with each other within an inclusive range of about 35 and about 45 degrees. In the example of Fig. 10, a longitudinal axis for each of the second wire segment 102B and the fourth wire segment 102D form an angle 102E form an angle of about 40 degrees. In some examples, a longitudinal axis for each of the second wire segment 102B and the fourth wire segment 102D form an angle 102E (Fig. 10) of about 39, 40, 41 , 42, 43, or 44 degrees. In some examples, a circle tangentially contacting the second wire segment 102B, the third wire segment 102C, and the fourth wire segment 102D has a diameter within an inclusive range of about 2.5 mm to about 13 mm. In some examples, a circle tangentially contacting the second wire segment 102B, the third wire segment 102C, and the fourth wire segment 102D has a diameter of about 3.7 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, or 4.4 mm.

[0113] The angles and radius of curvature noted above may be particularly beneficial for the ability to cut chordae and similar tissue within a heart chamber due to the limitedspace, orientation of the valve relative to other anatomical features such as chordae attachment locations, and the presence of heart valve therapy devices (e.g., valve leaflet clip 50). Put another way, the example angles and radius of curvatures of this example, as well as other examples in this specification, allow a user to navigate within a heart easier and more efficiently, which can reduce the time of a procedure and decrease possible complications (e.g., unintended cutting locations).

[0114] In some examples, the second wire segment 102B may have a length within an inclusive range of about 1.5 mm to about 16mm (or about 5.3 mm as shown), the third wire segment 102C may have a length within an inclusive range of about 1.5 mm to 9.5 mm (or about 3 mm as shown), and the fourth wire segment 102D may have a length within an inclusive range of about 1 .5 mm to 16 mm (or about 5 mm as shown).

[0115] The wire 104 of the tissue cutting catheter 100 may also include a radiopaque coil positioned over some or all of the length of the underlying shape-memory wire (e.g., Nitinol wire) to help improve visibility of the wire 104 under fluoroscopy. In some examples, the radiopaque coil is composed of tungsten. Any other example disclosed in this specification may use a similar technique to improve visibility.

[0116] Since a tissue cutting catheter may pass generally perpendicularly through a valve, it may be helpful for the memorized curved shape to have a more complicated shape that curves in multiple planes. For example, the memorized curved shape may form a generally helical or spiral shape, either as a continuous curvature or with discrete straight segments.

[0117] One example of such a more complex shape may be seen with the memorized clockwise curved shape 112 of the tissue cutting catheter 110. Fig. 15 illustrates a perspective view of a distal end of the tissue cutting catheter 110. Fig. 16 illustrates another perspective view of the tissue cutting catheter 110. Fig. 17 illustrates a side view of the tissue cutting catheter 110. Fig. 18 illustrates another side view of the tissue cutting catheter 110. Fig. 19 illustrates an end view of the tissue cutting catheter 110 looking ina distal direction. Fig. 20 illustrates an end view of the tissue cutting catheter 110 looking in a proximal direction. These figures will be discussed concurrently below.

[0118] The tissue cutting catheter 110 is generally similar to the previously described tissue cutting catheter 100 but with a memorized clockwise curved shape 112 that is different than the memorized curved shape 102. Put another way, the tissue cutting catheter 110 may be similar to the tissue cutting catheter 100 but where angle 112F (Fig. 18) is greater than 0 degrees vs. the 0 degrees flat shape of tissue cutting catheter 100 at the same viewing perspective.

[0119] In the present example, the memorized clockwise curved shape 112 may be made up of a plurality of straight segments that are angled relative to each other. A first wire segment 112A may be generally aligned or parallel to the longitudinal axis 110A. A second wire segment 112B extends from a distal end of the first wire segment 112A, a third wire segment 112C extends from a distal end of the second wire segment 112B at an angle within the same plane, and a fourth wire segment 112D extends from a distal end of the third wire segment 112C at an angle within the same plane.

[0120] In some examples, a longitudinal axis of the first wire segment 112A (e.g., the longitudinal axis 110A of the tissue cutting catheter 110) and a longitudinal axis of the second wire segment 112B form an angle 112F within an inclusive range of about 1 degree and about 90 degrees (see Fig. 18) in a first direction. In some examples, a longitudinal axis of the first wire segment 112A (e.g., the longitudinal axis 110A of the tissue cutting catheter 110) and a longitudinal axis of the second wire segment 112B form an angle 112F within an inclusive range of about 60 degrees and about 80 degrees (see Fig. 18) in a first direction. In some examples, a longitudinal axis of the first wire segment 112A and a longitudinal axis of the second wire segment 112B form an angle 112F within an inclusive range of about 65 degrees and about 75 degrees (see Fig. 18) in a first direction. In some examples, a longitudinal axis of the first wire segment 112A and a longitudinal axis of the second wire segment 112B may further form an angle within an inclusive range of about 15 degrees and about 25 degrees in a second direction that maybe about 90 degrees to the first direction (i.e., angles are formed along two different directions relative to the longitudinal axis 110A).

[0121] In some examples, a longitudinal axis of the third wire segment 112C is about perpendicular to the longitudinal axis 110A of the tissue cutting catheter 110. In some examples, a distal end of the fourth wire segment 112D is positioned further proximally than the third wire segment 112C. In some examples, the second wire segment 112B, the third wire segment 112C, and the fourth wire segment 112D are all generally positioned within the same plane, as seen best in Fig. 18. In that respect, the shape of the memorized clockwise curved shape 112 is similar to that of the memorized curved shape 102 except that the angle between a longitudinal axis of the first wire segment 112A and a longitudinal axis of the second wire segment 112B curves out of the plane of the remaining segments.

[0122] In some examples, a longitudinal axis for each of the second wire segment 112B and the fourth wire segment 112D form an angle 112E (Fig. 19) with each other within an inclusive range of about 0 and about 90 degrees. In some examples, a longitudinal axis for each of the second wire segment 112B and the fourth wire segment 112D form an angle 112E (Fig. 19) with each other within an inclusive range of about 35 and about 45 degrees. In the example of Fig. 19, a longitudinal axis for each of the second wire segment 112B and the fourth wire segment 112D form an angle 112E of about 40 degrees. In some examples, a longitudinal axis for each of the second wire segment 112B and the fourth wire segment 112D form an angle 112E (Fig. 19) of about 39, 40, 41 , 42, 43, or 44 degrees. In some examples, a circle tangentially contacting the second wire segment 112B, the third wire segment 112C, and the fourth wire segment 112D has a diameter within an inclusive range of about 2.5 mm to about 13 mm. In some examples, a circle tangentially contacting the second wire segment 112B, the third wire segment 112C, and the fourth wire segment 112D has a diameter of about 3.7 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, or 4.4 mm.

[0123] In some examples, the second wire segment 112B may have a length within an inclusive range of about 1 .5 mm to about 16 mm (or about 5.3 mm as shown), the thirdwire segment 112C may have a length within an inclusive range of about 1.5 mm to 9.5 mm (or about 3 mm as shown), and the fourth wire segment 112D may have a length within an inclusive range of about 1 .5 mm to 16 mm (or about 5 mm as shown).

[0124] At least some of the one or more electrodes 106 may be located at the apex of the memorized clockwise curved shape 112, such as the third wire segment 112C of the present example.

[0125] Another example of a more complex shape of a tissue cutting catheter may be seen with the memorized counterclockwise curved shape 122 of the tissue cutting catheter 120. Fig. 21 illustrates a perspective view of a distal end of the tissue cutting catheter 120. Fig. 22 illustrates another perspective view of the tissue cutting catheter 120. Fig. 23 illustrates a side view of the tissue cutting catheter 120. Fig. 24 illustrates another side view of the tissue cutting catheter 120. Fig. 25 illustrates an end view of the tissue cutting catheter 120 looking in a distal direction. Fig. 26 illustrates an end view of the tissue cutting catheter 120 looking in a proximal direction. These figures will be discussed concurrently below.

[0126] The tissue cutting catheter 120 is generally similar to the previously described tissue cutting catheter 100 but with a memorized counterclockwise curved shape 122 that is different than the memorized curved shape 102. Put another way, the tissue cutting catheter 120 may be similar to the tissue cutting catheter 100 but where angle 122F (Fig. 23) is greater than 0 degrees vs. the 0 degrees flat shape of tissue cutting catheter 100 at the same viewing perspective.

[0127] In the present example, the memorized counterclockwise curved shape 122 may be made up of a plurality of straight segments that are angled relative to each other. A first wire segment 122A may be generally aligned or parallel to the longitudinal axis 120A. A second wire segment 122B extends from a distal end of the first wire segment 122A, a third wire segment 122C extends from a distal end of the second wire segment 122B at an angle within the same plane, and a fourth wire segment 122D extends from a distal end of the third wire segment 122C at an angle within the same plane.

[0128] In some examples, a longitudinal axis of the first wire segment 122A (e.g., the longitudinal axis 120A of the tissue cutting catheter 120) and a longitudinal axis of the second wire segment 122B form an angle 122F within an inclusive range of about 1 degree and about 90 degrees (see Fig. 23) in a first direction. In some examples, a longitudinal axis of the first wire segment 122A (e.g., the longitudinal axis 120A of the tissue cutting catheter 120) and a longitudinal axis of the second wire segment 122B form an angle 122F within an inclusive range of about 60 degrees and about 80 degrees (see Fig. 23) in a first direction. In some examples, a longitudinal axis of the first wire segment 122A and a longitudinal axis of the second wire segment 122B form an angle 122F within an inclusive range of about 65 degrees and about 75 degrees (see Fig. 23) in a first direction. In some examples, a longitudinal axis of the first wire segment 122A and a longitudinal axis of the second wire segment 122B may further form an angle within an inclusive range of about 15 degrees and about 25 degrees in a second direction that may be about 90 degrees to the first direction (i.e., angles are formed along two different directions relative to the longitudinal axis 120A).

[0129] In some examples, a longitudinal axis of the third wire segment 122C is about perpendicular to the longitudinal axis 120A of the tissue cutting catheter 120. In some examples, a distal end of the fourth wire segment 122D is positioned further proximally than the third wire segment 122C. In some examples, the second wire segment 122B, the third wire segment 122C, and the fourth wire segment 122D are all generally positioned within the same plane, as seen best in Fig. 23. In that respect, the shape of the memorized counterclockwise curved shape 122 is similar to that of the memorized curved shape 102 except that the angle between a longitudinal axis of the first wire segment 122A and a longitudinal axis of the second wire segment 122B curves out of the plane of the remaining segments. The difference between the memorized clockwise curved shape 112 of the tissue cutting catheter 110 and the memorized counterclockwise curved shape 122 of the tissue cutting catheter 120 can be best seen by comparing the views of Figs. 19 and 25, which provide distally-facing views of the memorized shapes. In these views the memorized clockwise curved shape 112 appears to curve in aclockwise direction while the memorized counterclockwise curved shape 122 appears to curve in a counterclockwise direction.

[0130] In some examples, a longitudinal axis for each of the second wire segment 122B and the fourth wire segment 122D form an angle 122E (Fig. 25) with each other within an inclusive range of about 0 and about 90 degrees. In some examples, a longitudinal axis for each of the second wire segment 122B and the fourth wire segment 112D form an angle 122E (Fig. 25) with each other within an inclusive range of about 35 and about 45 degrees. In the example of Fig. 25, a longitudinal axis for each of the second wire segment 112B and the fourth wire segment 112D form an angle 112E of about 40 degrees. In some examples, a longitudinal axis for each of the second wire segment 122B and the fourth wire segment 122D form an angle 112E (Fig. 25) of about 39, 40, 41 , 42, 43, or 44 degrees. In some examples, a circle tangentially contacting the second wire segment 122B, the third wire segment 122C, and the fourth wire segment 122D has a diameter within an inclusive range of about 2.5 mm to about 13 mm. In some examples, a circle tangentially contacting the second wire segment 122B, the third wire segment 122C, and the fourth wire segment 122D has a diameter of about 3.7 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, or 4.4 mm.

[0131] In some examples, the second wire segment 122B may have a length within an inclusive range of about 1 .5 mm to about 16 mm (or about 5.3 mm as shown), the third wire segment 122C may have a length within an inclusive range of about 1 .5 mm to 9.5 mm (or about 3 mm as shown), and the fourth wire segment 122D may have a length within an inclusive range of about 1 .5 mm to 16 mm (or about 5 mm as shown).

[0132] At least some of the one or more electrodes 106 may be located at an apex of the memorized counterclockwise curved shape 122, such as the third wire segment 122C.

[0133] In the previously described examples of tissue cutting catheter 100, tissue cutting catheter 110, tissue cutting catheter 120, or other examples, the wire 104 may, in some examples, be a nitinol wire with a diameter of about .014 inches (0.36 mm). Eachof the one or more electrodes 106 may have an outer diameter of about 0.027 inches (0.69 mm) and a length of about 0.055 inches (1 .40 mm).

[0134] As previously described, the capture basket catheter 190 may be used to remove a heart therapy device (e.g., a valve leaflet clip 50) from a patient’s heart. Such a capture basket catheter 190 may include one or more additional unique features as described further below.

[0135] One unique aspect is the inclusion of flexible filaments, such as sutures, string, yam, wire, or similar components along a distal end of a mesh basket to help prevent openings of the mesh from increasing in size such that a heart therapy device (e.g., a valve leaflet clip 50) captured within may escape.

[0136] For example, Fig. 27 illustrates a side view of a capture basket catheter 130 that includes flexible filament 136 along a distal portion of a mesh basket 131. Fig. 28 illustrates an enlarged view of the mesh basket 131 of Fig. 27.

[0137] Generally, the capture basket catheter 130 is similarto the previously described capture basket catheter 190. The mesh basket 131 may be composed of one or more wires 135 that are braided together to form a basket shape with a proximally-facing opening. In some examples, a mesh tube may be first braided and then one end of the tube may be connected, fused, welded, or adhered together to form a basket tip 137 at a distal end of the mesh basket 131 .

[0138] The mesh basket 131 may form a plurality of loops along or near its proximal edge and around its proximal opening, through which a cinch wire 134 passes. The cinch wire 134 may pass into a passage of the elongated catheter body 132 and connect to an elongated control wire (or optionally just extend out a proximal end of elongated catheter body 132) so that a physician may proximally pull and decrease the diameter of the distal loop of the cinch wire 134 and the diameter of the proximally-facing opening of the mesh basket 131 .

[0139] Due to the braided nature of the mesh basket 131 , individual wires 135 (or segments thereof) may move relatively to each other to allow the mesh basket 131 to radially expand and contract. However, in some circumstances, it is possible that some individual wires 135 (or segments thereof) may be moved when the mesh basket 131 is in its radially expanded configuration, causing one of the openings / cells of the mesh basket 131 to increase in size. If the size is increased large enough, any contents of the mesh basket 131 , such as a valve leaflet clip 50, may escape.

[0140] The size of the openings / cells may be limited or restricted by including one or more flexible filaments 136. In some examples, a flexible filament 136 may be connected at a plurality of locations where the one or more wires 135 overlap with each other as part of the braiding pattern. In some examples, the flexible filament 136 may form a knot 136A or one or more loops around a crossing point of two segments of the one or more wires 135. The flexible filament 136 may form a plurality of knots 136A or loops at a plurality of different wire segment crossing locations. The knots 136A may help restrict movement of the wire segment crossing locations and the length of the flexible filament 136 between two knots 136A may further restrict movement. In that respect, it may be helpful to add the flexible filament 136 to the mesh basket 131 when the mesh basket 131 is in its expanded configuration.

[0141] The flexible filament 136 may extend laterally around a circumference of the mesh basket 131 between wire segment crossing points as seen in Fig. 28, forming lateral band patterns. The flexible filament 136 may additionally or alternatively extend longitudinally between wire segment crossing points.

[0142] In some examples, all or most of the wire segment crossing points along a distal quarter, distal third or distal half of the mesh basket 131 are restricted via knots 136A of the flexible filament 136. In some examples, all or most of the wire segment crossing points along the entire mesh basket 131 are restricted via knots 136A of the flexible filament 136.

[0143] The flexible filament 136 may be a single filament or may be a plurality of discrete filaments. The flexible filament 136 may be composed of relatively stretch resistant material or may be composed of a relatively elastic material. In some examples, the flexible filament 136 may be composed of a solid PET filament, a solid metal filament (e.g., Nitinol or radiopaque materials such as tantalum), a plurality of polymer yarn fibers (e.g., PET yarn / fibers), a surgical suture, a solid silicone filament, or other similar materials.

[0144] Fig. 29 illustrates a side view of the capture basket catheter 130 in use with a snare catheter 186 and a captured valve leaflet clip 50. The mesh basket 131 is in its radially expanded configuration as the snare catheter 186 moves the valve leaflet clip 50 towards the proximal opening of the mesh basket 131.

[0145] Fig. 30 illustrates the valve leaflet clip 50 positioned within the mesh basket 131 of the capture basket catheter 130. The flexible filament 136 helps restrict the size of the openings or cells of the mesh basket 131 so that the valve leaflet clip 50 is not accidentally pushed through the mesh basket 131.

[0146] Fig. 31 illustrates the proximal opening of the mesh basket 131 cinched closed by the cinch wire 134 around the snare catheter 186.

[0147] The capture basket catheter 130 may also or alternatively include a unique mounting arrangement to the elongated catheter body 132. Depending on how the elongated catheter body 132 may be connected to the mesh basket 131 , it may have a tendency for the capture basket catheter 130 to rotate so that a distal end of the capture basket catheter 130 is substantially out of alignment with an axis of the elongated catheter body 132. For example, if the capture basket catheter 130 rotates so that its opening opens perpendicular to the axis of the elongated catheter body 132 or even opens in a distal direction, it may be undesirable and may add difficulty for the physician attempting to align and / or capture a heart valve therapy device. Hence, it may be helpful in some circumstances to connect the mesh basket 131 and elongated catheter body 132 in a way to prevent or limit that type of rotating.

[0148] In one example, a distal tip member 133 of the elongated catheter body 132 may provide multiple connection points to the mesh basket 131 to help restrict movement between the components. Fig. 32 illustrates a side view of the distal tip member 133 and Fig. 33 illustrates another side view of the distal tip member 133 at about 90 degrees to the view of Fig. 32.

[0149] The distal tip member 133 may include a retaining portion comprising several discrete openings through its walls that allow both the cinch wire 134 and two segments of wires 135 to be captured.

[0150] In some examples, the distal tip member 133 may have a generally cylindrical, tubular shape 133A that is at least partially hollow. A distal end of the distal tip member 133 may include a rounded or atraumatic end portion 133E.

[0151] The distal tip member 133 may include two cinch wire openings 133D that are sized large enough to accommodate the cinch wire 134 positioned therethrough. In some examples, these two cinch wire openings 133D open into an internal passage of the elongated catheter body 132 which extends to a proximal end of the elongated catheter body 132 allowing a physician to pull and decrease a size of the loop created by the cinch wire 134..

[0152] The distal tip member 133 may also include two upper mesh wire openings 133B and two lower mesh wire openings 133C that are sized to allow segments of the one or more wires 135 to pass through and are positioned on sides of the distal tip member 133 to create two crisscrossing passages therethrough.

[0153] In some examples, the two upper mesh wire openings 133B and two lower mesh wire openings 133C are sized and positioned to capture two segments of the one or more wires 135 at a location of their crossing as part of their braid pattern. In that respect, one segment of the one or more wires 135 may pass through one of the two upper mesh wire openings 133B and one of the two lower mesh wire openings 133C on an opposite side as that upper mesh wire opening 133B. A second segment of the one or more wires 135 may similarly pass through the remaining of the two upper mesh wireopenings 133B and the two lower mesh wire openings 133C such that the two segments of the one or more wires 135 crisscross within an interior of the distal tip member 133. Since the two segments of the one or more wires 135 increase in distance on either side of the distal tip member 133 as seen in Fig. 32, the distal tip member 133 is restricted from both lateral and longitudinal movement relative to the mesh basket 131 .

[0154] Hence, the elongated catheter body 132 may maintain a constant rotational orientation relative to the mesh basket 131 during a procedure (i.e. , the mesh basket 131 will not substantially rotate out of alignment with an axis of the 132 and will maintain the opening into the cavity of the mesh basket 131 in a proximal direction). Additionally, this arrangement allows the distal tip member 133 to connect at both a more proximal location (i.e., two cinch wire openings 133D) and a more distal location (i.e., the two upper mesh wire openings 133B and two lower mesh wire openings 133C) which may help prevent the mesh basket 131 from rotating proximally towards the elongated catheter body 132 (i.e., flipping backwards). This arrangement also helps the mesh basket 131 to spring back to its original intended position relative to the elongated catheter body 132 when deflected during a procedure. Since it can be difficult to guide and use the mesh basket 131 during a procedure when it and its proximal opening are not relatively perpendicular to the elongated catheter body 132 (e.g., 45 degrees and 135 degrees relative to a longitudinal axis of the elongated catheter body 132), maintaining this “perpendicular” orientation can significantly improve navigation and capture times of a heart valve therapy device (e.g., valve leaflet clip 50).

[0155] Variations on the structure of the 133 are also possible. For example, instead of openings into the distal tip member 133, rings or tubes may instead be connected to an outside of the distal tip member 133 to create passages corresponding to the previously described openings. In another example, a wire or suture may be wound around a portion of the 133 and around the crossing point of the two segments of the one or more wires 135. In another example, the crossing point of the two segments of the one or more wires 135 may be adhered with adhesive or welded directly to the distal tip member 133.

[0156] In some examples, a capture basket catheter 130 may include either the flexible filament 136, the distal tip member 133, or both of the previously described features.

[0157] The devices shown and described in Figs. 1 -4 may be used to cut tissue immediately adjacent to a heart valve therapy device. In some cases, this tissue immediately next to the device (e.g., a valve leaflet clip 50) and the remaining portion of the mitral valve leaflets 14 is referred to as a tissue bridge. Other devices and techniques for cutting this tissue bridge are also possible.

[0158] Fig. 34 illustrates a side view of a tissue cutting device 140 that may be used for cutting a tissue bridge connecting a heart valve therapy device (e.g., valve leaflet clip 50). Fig. 35 illustrates a side view of the tissue cutting device 140 from a different side view that is about 90 degrees from the view of Fig. 34. Fig. 36 illustrates a perspective view of the tissue cutting device 140. These figures will be discussed concurrently below.

[0159] Generally, the tissue cutting device 140 has shape that allows it to be simultaneously positioned through valve, between leaflets, in two locations that are each on opposite sides of a valve leaflet clip 50. Hence, a portion of the tissue cutting device 140 may contact leaflet tissue adjacent to a connection point of a valve leaflet clip 50.

[0160] In some examples, the tissue cutting device 140 may comprise a core wire 142. A distal region of the core wire 142 is shown in the figures and either may connect to a larger elongated catheter body or may extend all the way to a proximal location. The core wire 142 may be composed of a shape memory material, such as Nitinol, and may have a memorized shape that forms a first curve 142A and a second curve 142B when the core wire 142 is unconstrained.

[0161] The first curve 142A may generally orient a distal end region of the core wire 142 at a location proximal to the first curve 142A. In some examples, the first curve 142A may curve within an inclusive range of about 160 to about 200 degrees. In some examples, the first curve 142A may curve within an inclusive range of about 170 to about 190 degrees. In some examples, the first curve 142A may curve at about 180 degrees.In some examples, the first curve 142A may orient portions of the core wire 142 immediately proximal and immediately distal in a generally parallel arrangement. In some examples, the first curve 142A has a diameter within an inclusive range of about 66 mm to about 18 mm.

[0162] The core wire 142 may include a snare attachment structure at or near a distal tip of the core wire 142 onto which a separate snare catheter may be connected within a heart as discussed later. In the present example, the snare attachment structure may take the form of the second curve 142B which may be located at or very near the distal tip of the 142B and may generally orient the distal tip of the core wire 142 at a location proximal to the second curve 142B. Alternatively, the snare attachment structure may instead be an enlargement (e.g., sleeve, coil, or welded mass) on the distal end of the core wire 142.

[0163] In some examples, the second curve 142B may curve within an inclusive range of about 160 to about 200 degrees. In some examples, the second curve 142B may curve within an inclusive range of about 170 to about 190 degrees. In some examples, the second curve 142B has a diameter within an inclusive range of about 2 mm to about 8 mm.

[0164] In some examples, the length of the core wire 142 between the first curve 142A and second curve 142B may be within an inclusive range of about 5 mm to about 15 mm.

[0165] In some examples, the core wire 142 may have a third curve 142C (Fig. 35) that may be generally perpendicular to the first curve 142A. The third curve 142C may optionally also overlap partially or fully with the first curve 142A. In some examples, the third curve 142C curves within an inclusive range of about 5 mm to about 12 mm, and may have a radius of curvature within an inclusive range of about 2 mm to about 10 mm. When the core wire 142 is positioned through a valve, the first curve 142A and third curve 142C may help achieve a position immediately adjacent to the valve leaflet clip 50 against valve leaflets, as described further below.

[0166] The length of the first curve 142A may include one or more electrodes 146. The present example provides three one or more electrodes 146 but more or less may be possible. The core wire 142 may be in electrical communication with a power source at a proximal end of the tissue cutting device 140. The distal region of the core wire 142 may be entirely covered with a layer of electrical insulation except at the electrodes 146. The electrodes 146 may be exposed areas of the core wire 142 without the electrical insulation layer or may be separate tubes, sleeves, or areas in contact with the core wire 142. The electrodes 146 may also be composed of a material that is more resistant to electrical or heat damage than Nitinol, such as stainless steel.

[0167] The tissue cutting device 140 may also include one or more radiopaque markers 144 connected on to the core wire 142. In one example, the one or more radiopaque markers 144 may be positioned such that, when in its unconstrained position, the second curve 142B is positioned parallel to or laterally adjacent to or laterally even with the second curve 142B (e.g., the one or more radiopaque markers 144 are positioned on a proximal segment of the core wire 142 that is generally parallel to a distal segment of the core wire 142 with the second curve 142B). This may allow the physician to better understand how far to position the core wire 142 through a valve and where the second curve 142B is located. The one or more radiopaque markers 144 may also be located at other positions, such as near the distal tip of the core wire 142.

[0168] In an alternative example, the second curve 142B may be replaced by an enlargement near the distal end of the core wire 142 which may prevent a snare catheter 186 from sliding off when engaged with the core wire 142.

[0169] An example method of using the tissue cutting device 140 will now be described. Fig. 37 illustrates a view of mitral valve leaflets 14 of a mitral valve within a left ventricle 12. A valve leaflet clip 50 is clipped onto both of the mitral valve leaflets 14. A sheath 109 may be positioned through the one side of the opening of the mitral valve leaflets 14.

[0170] Fig. 38 illustrates a view of mitral valve leaflets 14 of a mitral valve within a left ventricle 12. The core wire 142 is advanced out of the sheath 109 to expose the first curve 142A. In some examples, the core wire 142 may be packed into the sheath 109 such that the first curve 142A is retained within the passage of the sheath 109. This allows a small portion of the first curve 142A to be distally advanced out of the sheath 109 first. In other examples, the core wire 142 may be positioned straight within the sheath 109 so that the second curve 142B is the first portion of the core wire 142 to exit sheath 109.

[0171] Fig. 39 illustrates a view of mitral valve leaflets 14 of a mitral valve within a left ventricle 12. The first curve 142A of the core wire 142 may be positioned around the valve leaflet clip 50.

[0172] Figs. 40 and 41 illustrate views of the valve leaflet clip 50 on the mitral valve leaflets 14. The first curve 142A of the core wire 142 may be further moved to the “tissue bridge” or the area of leaflet tissue that is immediately adjacent to the valve leaflet clip 50. Hence, the electrodes 146 may also be located at this tissue bridge area. The third curve 142C may also be helpful for achieving this position.

[0173] Fig. 42 illustrates a view of the mitral valve leaflets 14 from the left atrium 10 side. The second curve 142B of the core wire 142 may be advanced through the opposite side of the valve leaflet clip 50 that the sheath 109 is / was passed through. In other words, a valve leaflet clip 50 may create at least two openings through the valve on either side of the valve leaflet clip 50. The portion of the core wire 142 proximal of the first curve 142A may be positioned through one side and the portion of the core wire 142 distal of the first curve 142A may be positioned through the other side. Hence, the second curve 142B is exposed within the left atrium 10 side of the valve.

[0174] Fig. 43 illustrates a view of the mitral valve leaflets 14 from the left atrium 10 side. Next, the previously described snare catheter 186 may be advanced out of the sheath 109 (or optionally a different, separate sheath) and the wire loop 186A may be positioned over the second curve 142B. As seen, the one or more radiopaque markers144 of the core wire 142 may provide a reference point at which to line of the wire loop 186A of the snare catheter 186 to “hook” on to the second curve 142B.

[0175] Fig. 44 illustrates a view of the mitral valve leaflets 14 from the left atrium 10 side. Next, the wire loop 186A of the snare catheter 186 may be pulled back proximally, decreasing the size of the wire loop 186A outside of the one or more openings 186B. This may better engage the second curve 142B with the wire loop 186A.

[0176] Fig. 45 illustrates a view of the mitral valve leaflets 14 from the left atrium 10 side. Next, the snare catheter 186 (and / or the sheath 109) may be pulled back proximally as electrical current (e.g., RF current) is supplied to the tissue cutting device 140. The electrical current may pass through the core wire 142 and out of the electrodes 146, cutting the tissue bridge adjacent to the valve leaflet clip 50 and freeing the valve leaflet clip 50 from the mitral valve leaflet 14. Typically, the tissue cutting device 140 will only separate the valve leaflet clip 50 from one leaflet (e.g., the anterior leaflet) in the case of the mitral valve. The valve leaflet clip 50 will typically remain attached to the other leaflet (e.g., posterior leaflet), but this will facilitate placement of an artificial replacement valve. The valve leaflet clip 50 typically will be trapped between the artificial valve frame and the posterior wall. If the valve leaflet clip 50 remained on the anterior leaflet it may swing into the LVOT during the heart cycle and therefore is typically undesirable. Additionally, the steps shown in figures 5-8 could be performed to completely remove the clip if desired. Thus if any challenge arises in the steps shown in figures 5-8, the physician could immediately convert the procedure to the valve implantation.

[0177] Depending on the type of procedure, it may be helpful to create relatively larger cuts, slits, or openings through leaflets (e.g., mitral valve leaflets 14). For example, leaflet cuts may be helpful for removing a valve leaflet clip 50 and / or modifying leaflet shapes prior to implantation of an artificial valve.

[0178] Fig. 46 illustrates a side view of a leaflet cutting system 150 that may comprise a leaflet cutting catheter 151 , a leaflet puncture tool 156, and a snare catheter 186. The leaflet cutting system 150 may be used in a similar manner to the tissue cutting device140 where the snare catheter 186 is used to pull a portion of the leaflet cutting catheter 151 through a portion of leaflet tissue.

[0179] The leaflet cutting catheter 151 may be similar to the previously described tissue cutting device 140. For example, the leaflet cutting catheter 151 comprises a core wire 152 similar to core wire 142 with a memory imparted shape that includes a first curve 152A similar to first curve 142A. In the present example, the core wire 152 includes an enlargement 152C (e.g. , a tube or welded portion) near a distal end of the core wire 152 in place of the second curve 142B of the core wire 142, however, either may be used with the core wire 152. The core wire 152 may also similarly include one or more electrodes 152B, similar to electrodes 146, that are located along the first curve 152A. Only one electrode152B is illustrated, but a plurality (e.g., similar to electrodes 146) are also possible. The core wire 152 may be connected to an electrical source either directly or indirectly via a catheter body it is attached to so that the one or more electrodes 152B may be selectively energized.

[0180] The leaflet puncture tool 156 of the leaflet cutting system 150 may be positioned over the leaflet cutting catheter 151 allowing it to first create a puncture through a leaflet. The leaflet puncture tool 156 may be a tubular catheter body with sharpened distal edge that may physically pierce a leaflet when pressed against it. Alternatively, the distal edge of the leaflet puncture tool 156 may include one or more electrodes that may be activated to puncture the leaflet.

[0181] The leaflet cutting system 150 may be used as follows. Fig. 47 illustrates a left ventricle 12 side of mitral valve leaflets 14. On the opposite left atrium 10 side of the mitral valve leaflets 14, a sheath 109 may be positioned and the leaflet puncture tool 156 may be distally moved out of the sheath 109. The distal edge of the leaflet puncture tool 156 may be pushed against the left atrium 10 side of one of the mitral valve leaflets 14 at a desired location such that the distal edge punctures through into the left ventricle 12, as seen in Fig. 47. Aspiration with a syringe through the passage of the leaflet puncture tool 156 may be used to hold the mitral valve leaflets 14 against the distal opening of the leaflet puncture tool 156 to facilitate cutting.

[0182] Fig. 48 illustrates another view of the left ventricle 12 side of the mitral valve leaflets 14. Next, the 152 may be advanced out of the leaflet puncture tool 156 and into the left ventricle 12 such that at least the enlargement 152C and the one or more electrodes 152B are exposed. Additionally, the wire loop 186A of the snare catheter 186 may be advanced through a separate existing opening within the valve, such as the native valve opening between mitral valve leaflets 14 or another previously cut slit / aperture.

[0183] Fig. 49 illustrates another view of the left ventricle 12 side of the mitral valve leaflets 14. As seen in the figure, the wire loop 186A may be placed around the core wire 152 of the leaflet cutting system 150 and tightened small enough that the enlargement 152C prevents the tightened wire loop 186A from sliding off the core wire 152. Next, both the core wire 152 and the snare catheter 186 (as well as optionally the leaflet puncture tool 156 and sheath 109) may be pulled proximally, which also pulls the one or more electrodes 152B against the left ventricle 12 side of the mitral valve leaflets 14. Electrical current (e.g., RF current) may be supplied to the core wire 152, passing down the core wire 152 and out the one or more electrodes 152B cutting the mitral valve leaflets 14.

[0184] Fig. 50 illustrates another view of the left ventricle 12 side of the mitral valve leaflets 14. The slit 14A can be seen in the figure after the core wire 152 has passed through the mitral valve leaflets 14. Depending on the nature of the treatment, this cutting procedure may be performed one or several times to achieve a desired opening or cut pattern.

Claims

What is claimed is:1 . A tissue cutting catheter for use within a heart, comprising: an elongated control member; wire connected to a distal portion of the elongated control member; wherein the wire has a memorized unconstrained shape forming a first curve; and, one or more electrodes positioned at an apex of the first curve.

2. The tissue cutting catheter of claim 1 , wherein the first curve comprises a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein the second wire segment and the fourth wire segment form an angle within an inclusive range of about 30 and about 50 degrees.

3. The tissue cutting catheter of claim 1 , wherein the first curve comprises a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein the second wire segment and the fourth wire segment form an angle within an inclusive range of about 35 and about 45 degrees.

4. The tissue cutting catheter of claim 1 , wherein the first curve comprises a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein a circle tangentially contacting the second wire segment, the third wire segment, and the fourth wire segment has a diameter within an inclusive range of about 2.5 mm to about5. The tissue cutting catheter of claim 1 , wherein the first curve comprises a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein a circle tangentially contacting the second wire segment, the third wire segment, and the fourth wire segment has a diameter within an inclusive range of about 3.7 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, or 4.4 mm.

6. The tissue cutting catheter of claim 1 , wherein the first curve comprises a first wire segment, a second wire segment connected to and extending from the first wire segment, a third wire segment connected to and extending from the second wire segment, and a fourth wire segment connected to and extending from the third wire segment; and wherein the first wire segment, the second wire segment, the third wire segment, and the fourth wire segment are positioned at different angles relative to each other.

7. The tissue cutting catheter of claim 6, wherein the first wire segment, the second wire segment, the third wire segment, and the fourth wire segment are positioned substantially within a same plane.

8. The tissue cutting catheter of claim 6, wherein the second wire segment, the third wire segment, and the fourth wire segment are substantially positioned within a first plane and wherein the first wire segment is substantially positioned within a second plane that is different than the first plane.

9. The tissue cutting catheter of claim 8, wherein the first curve is formed by the second wire segment, the third wire segment, and the fourth wire segment, and wherein the first curve curves in a substantially clockwise direction when viewed towards a distal direction.

10. The tissue cutting catheter of claim 8, wherein the first curve is formed by the second wire segment, the third wire segment, and the fourth wire segment, and whereinthe first curve curves in a substantially clockwise direction when viewed towards a distal direction.

11. The tissue cutting catheter of claim 8, wherein the first curve is formed by the second wire segment, the third wire segment, and the fourth wire segment, and wherein the first curve curves in a substantially counter-clockwise direction when viewed towards a distal direction.

12. The tissue cutting catheter of claim 6, wherein the wire is formed into a loop and wherein the loop forms the first wire segment, the second wire segment, the third wire segment, and the fourth wire segment.

13. A capture basket catheter for use within a heart, comprising: an elongated catheter body; a mesh basket formed of one or more wires braided together and connected at a distal portion of the elongated catheter body; and, at least one flexible filament connected at a plurality of locations on the mesh basket so as to limit sizes of cells of the mesh basket.1 . The capture basket catheter of claim 13, wherein the one or more wires braided together form a plurality of crossing wire segments; and wherein the at least one flexible filament forms a knot or loop around at least some of the crossing wire segments.

15. The capture basket catheter of claim 14, wherein the at least one flexible filament forms a circumferential pattern around the mesh basket.

16. The capture basket catheter of claim 15, wherein the at least one flexible filament also extends longitudinally along the mesh basket.

17. The capture basket catheter of claim 14, wherein the at least one flexible filament extends along a distal quarter, a distal third, or distal half of the mesh basket.

18. The capture basket catheter of claim 17, wherein the at least one flexible filament comprises a stretch resistant material or an elastic material.

19. The capture basket catheter of claim 18, wherein the at least one flexible filament comprises a solid PET filament, a solid metal filament, a plurality of polymer yarn fibers, or a solid silicone filament.

20. The capture basket catheter of claim 19, wherein the mesh basket includes an opening into a cavity of the basket that opens in a proximal direction when in an expanded configuration.

21. The capture basket catheter of claim 13, wherein the elongated catheter body further comprises a distal tip member comprising a retaining portion connected to a crossing point of two wire segments of the one or more wires.

22. The capture basket catheter of claim 21 , wherein the retaining portion comprises two upper mesh wire openings and two lower mesh wire openings; and wherein the two wire segments each pass through one of the two upper mesh wire openings and one of the two lower mesh wire openings.

23. The capture basket catheter of claim 22, wherein the distal tip member further comprises two cinch wire openings and wherein a cinch wire is positioned through the two cinch wire openings and through loops of the mesh basket.

24. A capture basket catheter for use within a heart, comprising: an elongated catheter body having; a mesh basket formed of one or more wires braided together; and, a distal tip member comprising a retaining portion connected to a crossing point of two wire segments of the one or more wires.

25. The capture basket catheter of claim 24, wherein the retaining portion comprises two upper mesh wire openings and two lower mesh wire openings; and wherein the two wire segments each pass through one of the two upper mesh wire openings and one of the two lower mesh wire openings.

26. The capture basket catheter of claim 25, wherein the distal tip member further comprises two cinch wire openings and wherein a cinch wire is positioned through the two cinch wire openings and through loops of the mesh basket.

27. The capture basket catheter of claim 26, wherein the two upper mesh wire openings and the two lower mesh wire openings are located distally of the two cinch wire openings.

28. A tissue cutting device for use within a heart, comprising: an elongated catheter body; a core wire connected to a distal end of the elongated catheter body; the core wire comprising a memorized shape when unconstrained that forms a first curve, a snare attachment structure at or near a distal tip of the core wire, and one or more electrodes positioned along the first curve.

29. The tissue cutting device of claim 28, wherein the first curve is within an inclusive range of about 160 to about 200 degrees.

30. The tissue cutting device of claim 29, wherein the snare attachment structure is a second curve of the core wire, a sleeve, a coil, or a weld mass.

31. The tissue cutting device of claim 30, further comprising a radiopaque marker positioned on a proximal segment of the core wire at a location laterally even with the snare attachment structure.

32. The tissue cutting device of claim 28, further comprising a leaflet puncture tool positioned over the elongated catheter body and the core wire.

33. A method of removing a heart valve therapy device; comprising: positioning a core wire of a tissue cutting catheter from a first side of a valve through to a second side of the valve; looping a first curve of the core wire around the heart valve therapy device on the second side of the valve; positioning a snare attachment structure on a distal region of the core wire back through to the first side of the valve; engaging a snare catheter with the snare attachment structure; and, activating one or more electrodes along the first curve of the core wire to separate the heart valve therapy device from leaflets of the valve.

34. A method of modifying a heart leaflet; comprising: puncturing a heart leaflet with a leaflet puncture tool to create a first opening; positioning a core wire of leaflet cutting catheter from a first side of a valve through to a second side of the heart valve; positioning a snare loop of a snare catheter through a second opening of the heart valve to the second side of the heart valve; engaging the snare loop with a snare attachment structure of a distal region of the core wire; and, activating one or more electrodes along the core wire while pulling the leaflet cutting catheter and the snare catheter to cut the heart leaflet.

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