Heart valve ablation catheter

Abstract

Cardiac annuloplasty methods and devices are based on delivering tissue ablation energy to a cardiac valve annulus, thereby inducing a reduction in the circumference of the annulus. In some embodiments, the reduction is induced by tissue contraction in response to the ablation, potentially similar to the tissue contraction involved in pulmonary vein stenosis induced by cardiac ablation to treat atrial fibrillation. In some embodiments, the annulus tissue is deformed before the ablation energy is applied, potentially resulting in plastic deformation separate from the tissue contraction. The deformation is performed using electrodes, which optionally also operate as sharp-tipped jaws of pliers, inserted into the tissue in a more widely spaced configuration, reduced in distance to a more closely spaced tissue-compressing configuration, and manipulated to ablate the compressed tissue. Upon removal of the electrodes, the compressed tissue retains its new shape as a result of the ablation-induced plastic deformation.

Description

[Technical Field]

[0001] [Related Applications] This application claims the benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63 / 111,033, filed November 8, 2020, the contents of which are incorporated herein by reference in their entirety. [Background technology]

[0002] The present invention, in some embodiments thereof, relates to the field of structural heart disease, and more particularly, but not exclusively, to heart annuloplasty.

[0003] Patients suffering from inadequate heart valve function (e.g., of the mitral valve) may undergo implantation of an annuloplasty ring sutured to the annulus fibrosus tissue of the heart valve. The purpose is to reduce and / or stabilize the valve circumference. The procedure may be performed as open-heart surgery or via an intravascular (transcatheter) approach with several devices.

[0004] As the valve circumference decreases, the leaflets come closer together and therefore achieve a better seal (coaptation) to reduce or eliminate valve regurgitation. Summary of the Invention [Means for solving the problem]

[0005] According to an aspect of some embodiments of the present disclosure, there is provided a method of performing a cardiac annuloplasty procedure comprising delivering energy around a cardiac valve annulus in an amount sufficient to structurally disrupt tissue and induce contraction around the annulus to reduce regurgitant flow through the cardiac valve.

[0006] According to some embodiments of the present disclosure, the structural disruption of the tissue comprises changes to the fibrous structure of the tissue.

[0007] According to some embodiments of the present disclosure, the energy destroys the tissue of the heart valve annulus while the tissue is in its mechanically deformed state.

[0008] According to some embodiments of the present disclosure, the mechanically deforming comprises compressing the tissue.

[0009] According to some embodiments of the present disclosure, compressing the tissue includes piercing the tissue with at least one sharp element and manipulating the sharp element to apply compression.

[0010] According to some embodiments of the present disclosure, the at least one sharp element also includes an element used to deliver structural disruptive energy to tissue.

[0011] According to some embodiments of the present disclosure, the element is an electrode.

[0012] According to some embodiments of the present disclosure, the electrodes destroy tissue structures by transmitting RF energy into the tissue.

[0013] According to some embodiments of the present disclosure, the electrodes disrupt tissue architecture by inducing cell death.

[0014] According to some embodiments of the present disclosure, the electrodes destroy tissue structure by coagulation.

[0015] According to some embodiments of the present disclosure, compressing includes pinching the tissue between a plurality of at least one sharp element.

[0016] According to some embodiments of the present disclosure, compressing includes applying a twist to the tissue using at least one sharp element.

[0017] According to some embodiments of the present disclosure, the reduction in annular circumference includes tissue shrinkage as a result of the delivery of tissue ablation energy.

[0018] According to some embodiments of the present disclosure, the reduction in annular circumference comprises plastic deformation of the tissue as a result of delivery of tissue ablation energy while the tissue is mechanically deformed.

[0019] According to some embodiments of the present disclosure, delivering tissue ablation energy includes delivering radio frequency energy into the perforated tissue via the electrodes.

[0020] According to some embodiments of the present disclosure, delivering tissue ablation energy includes delivering radio frequency energy into the contacted tissue via the electrodes.

[0021] According to some embodiments of the present disclosure, the tissue ablation energy is provided by at least one of the group consisting of radiofrequency energy, focused ultrasound energy, and cryogenic cooling.

[0022] According to some embodiments of the present disclosure, the tissue ablated includes at least one of the group consisting of fibrous tissue of the valve annulus and tissue of the heart wall adjacent to the fibrous tissue of the valve annulus.

[0023] According to some embodiments of the present disclosure, the annulus is a mitral or tricuspid annulus.

[0024] According to some embodiments of the present disclosure, the method includes repeating the delivery of tissue ablation energy at multiple sites around the circumference of the heart valve annulus.

[0025] According to some embodiments of the present disclosure, a method includes selecting a patient having a dilated cardiac valve periphery, planning a targeted reduction of the periphery of the cardiac valve annulus including selecting locations along the cardiac valve annulus to be targeted for contraction, and delivering energy at each of the selected locations.

[0026] According to some embodiments of the present disclosure, at least a portion of the contraction occurs during a cardiac annuloplasty procedure.

[0027] According to some embodiments of the present disclosure, at least a portion of the contraction occurs after a cardiac annuloplasty procedure.

[0028] According to an aspect of some embodiments of the present disclosure, there is provided a method of performing cardiac annuloplasty, the method including perforating tissue along a circumference of a cardiac valve with at least one electrode; applying a mechanical force to the at least one electrode to deform the perforated tissue and reduce the circumference of the cardiac valve annulus; delivering tissue ablation energy via the electrode, thereby inducing plastic deformation of the deformed tissue; and releasing the mechanical force to leave the cardiac valve annulus with a reduced circumference.

[0029] According to some embodiments of the present disclosure, applying a mechanical force includes applying a torsion to the perforated tissue.

[0030] According to some embodiments of the present disclosure, applying a mechanical force includes compressing the perforated tissue.

[0031] According to some embodiments of the present disclosure, the tissue ablation energy is radiofrequency energy.

[0032] According to some embodiments of the present disclosure, delivering tissue ablation energy induces plastic deformation by coagulation.

[0033] According to some embodiments of the present disclosure, the reduced perimeter draws the leaflets of the heart valve into a position that reduces regurgitation of the valve.

[0034] According to some embodiments of the present disclosure, reducing regurgitation includes restoring coaptation between the leaflets of the heart valve.

[0035] According to some embodiments of the present disclosure, plastic deformation includes contraction of the deformed tissue.

[0036] In accordance with an aspect of some embodiments of the present disclosure, there is provided an apparatus for valvuloplasty treatment, comprising a catheter sized for transvascular insertion into a cardiac chamber through a percutaneous incision to reach a cardiac valve annulus thereof, and at least one tissue-penetrating element at a distal end of the catheter, the at least one penetrating element moving relative to the body of the catheter and operative to deliver tissue-disrupting energy to the penetrating tissue of the cardiac valve annulus.

[0037] According to some embodiments of the present disclosure, the at least one piercing element comprises a plurality of piercing elements whose relative distance is adjustable while inserted into the tissue of the heart valve annulus.

[0038] According to some embodiments of the present disclosure, each of the at least one tissue-penetrating element is an electrode that is electrically interconnected to a connection that remains outside the percutaneous incision when the catheter is inserted into the heart chamber.

[0039] According to some embodiments of the present disclosure, each of the plurality of piercing elements operates as an ablation electrode.

[0040] According to some embodiments of the present disclosure, the piercing elements are inserted into tissue at a relatively wide distance and spaced apart to adjust to a narrower distance.

[0041] According to some embodiments of the present disclosure, the relative distance of the piercing elements is adjusted by rotation of a gear.

[0042] According to some embodiments of the present disclosure, the gear is rotated by a control element leading to the proximal side of the catheter.

[0043] According to some embodiments of the present disclosure, the control element also acts to provide an electrical interconnection between at least one of the tissue-piercing elements and a power source that remains outside the percutaneous incision.

[0044] According to some embodiments of the present disclosure, the relative distance of the piercing elements is adjusted by temperature changes of an actuator that includes a shape memory alloy.

[0045] According to some embodiments of the present disclosure, the shape memory alloy is arranged such that a temperature change is induced by heating as a result of the piercing element operating as an electrode.

[0046] According to some embodiments of the present disclosure, the shape memory alloy is shaped to cause the penetrating element to move from an initial distance to a relatively small distance when heated.

[0047] According to some embodiments of the present disclosure, the device includes a device reset operable to restore the distance of the penetrating element to before the temperature change while the device remains inserted into the heart chamber.

[0048] According to some embodiments of the present disclosure, the device includes an inner component that terminates distally within the energy delivery segment and is housed within an outer tube, the outer tube being sized for insertion into a heart chamber from within a guide catheter, the outer tube having a predetermined distal bend that it assumes when not restricted by the guide catheter and that straightens when the outer tube is retracted into the guide catheter.

[0049] According to some embodiments of the present disclosure, the at least one penetrating element has a non-circular cross-section that engages and induces a twist in the tissue into which it is inserted when subjected to torque applied via the catheter.

[0050] According to some embodiments of the present disclosure, the device has an inner component that terminates distally in a tissue ablation segment and is housed within an outer tube, the outer tube being sized for insertion into a cardiac chamber from within a guide catheter, the outer tube having a predetermined distal bend that it assumes when not restricted by the guide catheter and that straightens when the outer tube is retracted into the guide catheter.

[0051] According to some embodiments of the present disclosure, the non-circular cross section comprises a rectangular blade.

[0052] According to some embodiments of the present disclosure, the non-circular cross-section includes three or more blades extending radially from a central axis.

[0053] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs.Although methods and materials similar or equivalent to those described herein can be used in carrying out or testing the embodiments of this disclosure, exemplary methods and / or materials are described below.In case of conflict, this patent specification, including definitions, will prevail.In addition, materials, methods, and examples are merely illustrative and are not necessarily intended to be limiting. [Brief explanation of the drawings]

[0054] Some embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings. Referring now in detail to the drawings, it will be stressed that the specific details shown are by way of example and are for the purpose of illustrating embodiments of the invention. In this regard, the description taken with the drawings will make apparent to those skilled in the art how embodiments of the invention may be practiced.

[0055] [Figure 1] 1A and 1B are flow charts that schematically illustrate heart valve annulus processing, according to some embodiments of the present disclosure. [Figure 2A] 1A and 1B illustrate schematically an electrical monopolar ablation system according to some embodiments of the present disclosure. [Figure 2B] 1A and 1B illustrate schematically a bipolar ablation system according to some embodiments of the present disclosure. [Figure 3]Schematically illustrates distal elements of an ablation catheter (optionally an example of an RF ablation catheter, or an ablation catheter using another ablation energy type, e.g., a cryoablation catheter or a focused ultrasound ablation catheter), particularly related to steering, according to some embodiments of the present disclosure. [Figure 4] Schematically illustrates distal elements of an ablation catheter (optionally an example of an RF ablation catheter, or an ablation catheter using another ablation energy type, e.g., a cryoablation catheter or a focused ultrasound ablation catheter), particularly related to steering, according to some embodiments of the present disclosure. [Figure 5] Schematically illustrates distal elements of an ablation catheter (optionally an example of an RF ablation catheter, or an ablation catheter using another ablation energy type, e.g., a cryoablation catheter or a focused ultrasound ablation catheter), particularly related to steering, according to some embodiments of the present disclosure. [Figure 6] 1A-1C are schematic illustrations of the steering of an ablation catheter within a heart chamber (left atrium) according to some embodiments of the present disclosure. [Figure 7] 1A-1C are schematic illustrations of the steering of an ablation catheter within a heart chamber (left atrium) according to some embodiments of the present disclosure. [Figure 8] 8A-8D schematically illustrate additional configurations of various ablation catheters that allow for ablation at any location along the annulus, according to some embodiments of the present disclosure. [Figure 9] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 10] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 11]10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 12] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 13] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 14] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 15] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 16] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 17] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 18] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 19] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 20] 10A-10C schematically illustrate alternative designs of inner components for use with RF ablation systems, according to some embodiments of the present disclosure. [Figure 21] 21A and 21B schematically illustrate a method of shaping tissue by ablation while the tissue is in compression or traction, according to some embodiments of the present disclosure. [Figure 22]1A-1C are schematic illustrations of a method of shaping tissue by ablation while the tissue is in compression or traction, according to some embodiments of the present disclosure. [Figure 23] 1A-1C are schematic illustrations of a method of shaping tissue by ablation while the tissue is in compression or traction, according to some embodiments of the present disclosure. [Figure 24] 24A and 24B schematically illustrate a method of shaping tissue by ablation while the tissue is in compression or traction, according to some embodiments of the present disclosure. [Figure 25] 1A-1C are schematic illustrations of a method of shaping tissue by ablation while the tissue is in compression or traction, according to some embodiments of the present disclosure. [Figure 26] 1A and 1B illustrate schematic diagrams of electrode pliers according to some embodiments of the present disclosure. [Figure 27A] 1A and 1B illustrate schematic diagrams of electrode pliers according to some embodiments of the present disclosure. [Figure 27B] 1A and 1B illustrate schematic diagrams of electrode pliers according to some embodiments of the present disclosure. [Figure 28A] 27A-27C, according to some embodiments of the present disclosure. [Figure 28B] 27A-27C, according to some embodiments of the present disclosure. [Figure 28C] 27A-27C, according to some embodiments of the present disclosure. [Figure 29] 10A-10C schematically illustrate the positioning via an endovascular approach of a distal portion of an ablation catheter used for mitral valve annuloplasty, according to some embodiments of the present disclosure. [Figure 30] 10A-10D demonstrate an optional proximal side of a catheter according to some embodiments of the present disclosure. [Figure 31]31A-31E schematically illustrate different constructed layers of an adjustable width ablation catheter, according to some embodiments of the present disclosure. [Figure 32] 10A-10C illustrate an exploded view of a tube and / or a self-interlocking pattern cut to provide flexibility to the tube, according to some embodiments of the present disclosure. [Figure 33] 10A-10C schematically depict an ablation electrode configuration for insertion into tissue, twisting, and then ablation, according to some embodiments of the present disclosure. [Figure 34] 34A-34D illustrate a twisting and ablation method for perivalvular reduction according to some embodiments of the present disclosure. [Figure 35] 35A-35B schematically illustrate configurations of electrode assemblies comprising two needle electrodes interconnected by a loop spring, according to some embodiments of the present disclosure. [Figure 36-1] 36A-36C schematically illustrate configurations of mechanically actuated electrode assemblies comprising two needle electrodes interconnected by a loop spring, according to some embodiments of the present disclosure. [Figure 36-2] 36D and 36E schematically illustrate configurations of mechanically actuated electrode assemblies comprising two needle electrodes interconnected by a loop spring, according to some embodiments of the present disclosure. [Figure 37] 37A-37C schematically illustrate the operation of the mechanically actuated electrode assembly of FIGS. 36A-36E, according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0056] The present invention, in some embodiments thereof, relates to the field of structural heart disease, and more particularly, but not exclusively, to heart annuloplasty.

[0057] overview An aspect of some embodiments of the present disclosure relates to annuloplasty performed using tissue contraction and / or remodeling induced by energy applied to the region of the annular ring of the valve.

[0058] Currently, the gold standard of care for treating atrial fibrillation is the use of RF energy to ablate an area along the left atrial wall around the pulmonary veins. A reported side effect of this procedure is pulmonary vein stenosis (PVS).

[0059] PVS can also be the result of ablation procedures performed using other methods, such as cryoablation (e.g., as reported by J. Matsuda et al., J Cardiovasc Electrophysiol. 2017 Mar;28(3):298-303. Pulmonary vein stenosis after second-generation cryoballoon ablation).

[0060] PVS results from pulmonary vein constriction induced by the contraction of the ablated tissue area. The physiological mechanism by which ablation causes pulmonary vein stenosis is due to scarring of the connective tissue surrounding the pulmonary vein, as described, for example, in Pulmonary Vein Stenosis After Catheter Ablation, Electroporation vs. Radiofrequency by Vincent JAM et al., Circ Arrhythm Electrophysiol. 2014 Aug;7(4):734-8.

[0061] We describe herein an endovascular approach that uses the phenomenon of tissue contraction induced by the application of structural disruption energy to treat cardiac valve leakage. Leakage is characterized by malcoaptation of the cardiac valve leaflets, which do not close completely in response to back pressure. This allows for backflow of blood, impairing the efficiency of pumping by the heart.

[0062] In some embodiments of the present disclosure, tissue surrounding the valve annulus is remodeled by application of structural disruptive energy, which in some embodiments includes energy sufficient to ablate the tissue. The ablation may directly lesion the annular tissue (i.e., ablation lesion of the fibrous tissue of the annulus) and / or may lesion nearby tissue, such as the atrial wall above the mitral or tricuspid valve.

[0063] Ablation induces contraction and a corresponding reduction in the overall circumference of the valve annulus. This can potentially reduce the severity of regurgitation by bringing the leaflets of a regurgitating heart valve into coaptation, or, if coaptation is not achieved, by reducing the remaining gap between them in their fully closed state. In some cases, the initial loss of normal leaflet coaptation was itself caused by remodeling (stretching) of the valve annulus. Therefore, treatments that constrict the valve annulus may return the heart valves to their original relationship with each other.

[0064] As used herein, reference to "ablation" of tissue refers to the delivery of structurally disruptive energy to the tissue that induces cell death in at least the tissue while generally preserving (but possibly altering) the integrity of the tissue's connective structures. Furthermore, within the context of the embodiments described herein, the ablation performed has at least one of the following two: The ablated tissue shrinks. The ablated tissue undergoes plastic remodeling to a shape influenced by the mechanical forces applied to the tissue during and / or after ablation.

[0065] Without commitment to a particular theory, these effects may result, for example, from loss of cellular structure, from relaxation of internal stresses on connective fibers, from degenerative (coagulation) effects on tissue structures that persist after ablation, and / or from the effects of healing processes that occur after ablation.

[0066] Contraction can include effects that occur immediately or near immediately (e.g., due to loss of fluid or shrinkage of cellular components), as well as slower effects due, for example, to induced atrophy and / or healing processes.

[0067] In some embodiments, the application of structural disruptive energy is optionally sub-ablative. For example, the fibrous structure of tissue can be made more malleable by heating and / or adjusting its pH by passing an electrolytic current. This malleable structural disruption can be induced simultaneously with or separately from tissue contraction.

[0068] The effects of plastic remodeling under mechanical forces described in the embodiments herein are generally acute; that is, they occur during the application of structural disruption energy or within subsequent cycles while the procedure using a tool to apply the mechanical force is ongoing. Without commitment to a particular theory, these acute effects can be understood as being influenced by the disintegrating effect of coagulation, which acts to relieve stress and / or strain in tissue deformed by external mechanical forces. This effectively gives the tissue a new "preferred shape" in the coagulated state even after the external mechanical force is removed (i.e., plastically deformed). It is not excluded that there may be non-coagulation mechanisms that affect plastic deformation when structural disruption energy is applied to tissue deformed by external forces. For example, it has been proposed that electrolysis of water in the tissue region results in the production of free protons, which temporarily affects the self-bonding of the collagen matrix, resulting in the collagen matrix becoming more malleable.

[0069] The two main types of ablation performed on cardiac tissue to treat atrial fibrillation are thermal ablation, using radiofrequency (RF) or ultrasound energy, and cryoablation. Both types of ablation are associated with pulmonary vein stenosis. However, differences in the two mechanisms may result in differences in tissue remodeling effects. For example, the effect of thermal ablation involves coagulation, which acts directly on structural cellular components, whereas the primary effect of cryoablation is to destroy cellular tissue and processes, potentially under biological control, leading to downstream degeneration of structural cellular components. Electroporation is another cellular ablation mechanism that is primarily destructive in its initial effect rather than denaturation (coagulation). Electrolysis of tissue water has also been proposed as a mechanism to disrupt the collagen matrix by partially acidifying it.

[0070] In some embodiments, valvuloplasty is performed by structural destruction of tissue, reducing valve circumference by approximately 5-10%. Remodeling of the annulus can be targeted to sites at any selected portion of the circumference of the annulus, for example, by destroying tissue at approximately evenly spaced locations, or alternatively, by destroying tissue at locations grouped in one or more specific regions around the circumference.

[0071] An aspect of some embodiments of the present disclosure relates to methods and devices for mechanically deforming tissue while also applying constructive disruptive energy to shrink and / or make the tissue more malleable. In some embodiments, the tissue is deformed by the application of mechanical force. In some embodiments, the deformation is used to affect the tissue remodeling effects of ablation or sub-ablative application of constructive disruptive energy to perform annuloplasty.

[0072] The effects of mechanical tissue deformation can be distinguished from the effects of delivering structural disruption energy insofar as the mechanical tissue deformation (when applied without additional structural disruption energy) reverses when the mechanical force that induces it is removed. In other words, mechanical tissue deformation is solely elastic, while the application of structural disruption energy "plasticizes" the tissue, making it malleable to a new, inelastically reversible shape upon deformation and / or directly inducing plastic deformation in the tissue. References herein to "disruption" of tissue refer to the inelastic structural disruption of the tissue, with or without cell death. It should be understood that the disruption referred to is a partial disruption that modifies but maintains the overall structural integrity of the tissue.

[0073] Modalities that deliver structurally disruptive energy to tissue (such as RF ablation and / or application of electrical current) can induce remodeling of tissue deformed by the mechanical force into a new shape that persists when the mechanical force causing the tissue deformation is removed. This type of plastic deformation is distinct from plastic deformation due to contraction of ablated tissue, and both effects can occur.

[0074] In some embodiments, the mechanical force is applied by compressing the tissue between multiple laterally separated elements, each of which is also referred to herein as a "jaw," and which act together as a tissue pliers. The jaws are sized for manipulation of the valve annulus, e.g., having a maximum width of less than 0.2 mm, less than 0.4 mm, less than 0.8 mm, or less than 1 mm (e.g., a 0.4 mm x 0.4 mm cross section) and a length of about 1 to 10 mm, e.g., 2 mm, 3 mm, or 4 mm. The maximum distance between the jaws may be, for example, in the range of about 2 to 10 mm, e.g., 2 mm or 4 mm.

[0075] The jaws of the tissue pliers may be applied to or may pierce a tissue surface. As the jaws move toward each other, the tissue is compressed, resulting in a deformation of its shape. Energy applied to the tissue in this state (e.g., in the form of heating, cooling, and / or electrical energy) may tend to relieve the internal forces of that deformed shape as the tissue components are altered, e.g., coagulated and / or dissociated.

[0076] The jaws of the tissue pliers are optionally actuated by rotational motion commanded through a wire or shaft that connects the tissue pliers through the catheter to a control actuator that remains outside the body (e.g., outside the percutaneous incision through which the catheter was inserted). For example, a rack and pinion arrangement can convert rotation of a pinion gear into linear motion of the jaws. Alternatively, the jaws are connected by ties to a central member that is rotated by a wire or shaft and are spring-loaded to remain separated until the central member rotates, wrapping the ties shorter and bringing the jaws together.

[0077] In some embodiments, jaw movement is automatically triggered by heating the device during operation to deliver energy to the target tissue. This may be implemented, for example, using a shape memory alloy spring that is initialized in a first state (e.g., a jaw separation state) while soft and below its transition temperature. The preset shape of the spring in a superelastic state (above the alloy's transition temperature) is selected to drive the jaws into a closer position. After cooling, the device can be reset, for example, by using a reshaping device such as a wedge. Alternatively, a second elastic member may be provided that is weaker than the shape memory alloy spring when the shape memory alloy spring is above its transition temperature, but stronger when the shape memory alloy spring is below its transition temperature.

[0078] Additionally or alternatively, in some embodiments, mechanical force is applied by inducing a twist in (twisting) a tissue region. The twist can be applied by twisting pliers engaged with the tissue (effectively using it as a wrench, with the pliers jaws doubling as wrench jaws). In another wrench-like configuration, multiple fixed jaws (which are not used as pliers because they are fixed) can be re-engaged with the tissue (e.g., by piercing it). Twisting these jaws around a common center induces a twist in the surrounding tissue.

[0079] Optionally, a single rod-shaped element is used as a wrench to twist the surrounding tissue. This can include a tissue-piercing element, with a cross-sectional profile such that a portion of its surface presses against the tissue as the single element is rotated. This can be the result of some portions of the cross-sectional profile having adjacent regions around the periphery at a sharply exaggerated relative radial measurement distance from the center of the cross-sectional profile (i.e., a rapid transition from wider to narrower). A narrow rectangular cross-section (e.g., blade-shaped) provides one example. Because tissue is somewhat elastic, there may be a limit to the blade torque force sufficient to rotate the blade without dragging the tissue along with it before an opening opens. Related cross-sectional shapes that can be used are a star-shaped or a chevron shape (e.g., with three, four, or more blades radiating from a common central axis; flat blades can each be thought of as having two blades radiating from a common center). This can allow for somewhat higher torque levels before slippage occurs. The maximum diameter of the portion of the device that is inserted into the tissue may be, for example, about 2-6 mm.

[0080] In some embodiments, delivery of the structural disruptive energy is performed using at least one of the same elements that comprise the pliers and / or wrench jaws, e.g., one or more of the jaws also operate as ablation electrodes.

[0081] Energy may alternatively be delivered by an energy delivery element (e.g., an electrode of an electrode probe, focused ultrasound probe, or cryoablation probe) placed on or in tissue deformed by another tool. This offers a potential advantage by allowing for the area of ​​highest applied force to be optionally separated from the area receiving the highest energy. The area receiving the most structurally disruptive energy may also be the area that is thereby most weakened, which weakening may result in unintended tearing.

[0082] Before describing at least one embodiment of the present disclosure in detail, it is to be understood that the disclosure is not necessarily limited in its application to the details of construction and arrangement of components and / or methods set forth in the following description and / or illustrated in the drawings. Features described in the present disclosure, including inventive features, are capable of other embodiments or of being practiced or carried out in various ways.

[0083] background 1A and 1B, which are flow charts that generally illustrate methods of cardiac valve annulus treatment, according to some embodiments of the present disclosure. The operations of the blocks in Figures 1A and 1B are substantially the same, except that Figure 1B adds block 111 for operations that deform the annulus tissue.

[0084] At block 110, in some embodiments, an energy delivery tool (e.g., an ablation electrode or other probe capable of delivering structure-disruptive energy) is positioned at a predetermined location along the circumference of the valve annulus that includes contact with the annular tissue that is to be contracted as part of an annuloplasty procedure that seeks to improve valve function by reducing the overall circumference of the annulus.

[0085] The energy delivery tool may include, for example, an electrode configured to deliver radio frequency (RF) energy to tissue, a focused ultrasound transducer, or a cryoablation probe. Examples of ablation systems are described, for example, in connection with FIGS. 2A, 2B, and 30. Other figures illustrate embodiments of probes used to deliver structurally disruptive energy. FIGS. 3-8D and 29 particularly illustrate probes with control degrees of freedom that allow access to different portions around the annulus by contact with the energy delivery portion (e.g., electrode) of the catheter.

[0086] Placement of block 110 may include placing one or more electrodes on the tissue targeted for modification and / or inserting one or more electrodes into the tissue targeted for modification. Figures 9-20 show different electrode probe designs, some of which are inserted into the tissue, some of which rest on the tissue, and some of which combine the two with different electrodes and / or electrode portions.

[0087] In block 111, in some embodiments (FIG. 1B), the tissue targeted for modification (e.g., on the periphery of the valve annulus) is mechanically deformed. In some embodiments, this is performed by manipulating the position of one or more electrodes already inserted into the target tissue in block 110. For example, the electrodes may be squeezed together, squeezing the tissue between them. Preferably, the electrodes are oriented (e.g., substantially tangential to the periphery of the annulus) so that squeezing them together shortens the periphery of the annulus. Additionally or alternatively, the electrodes (individually and / or as a group) are rotated, straining the tissue to shorten a distance along the periphery of the annulus.

[0088] Figures 21A-28, 31A-32, and 35A-37C show probes operable to deform target tissue by squeezing the target tissue between two electrodes, and Figures 33-34D illustrate probes with electrodes that can be rotated to deform the target tissue.

[0089] In block 112, in some embodiments, tissue undergoes structural disruption, e.g., ablation, by application of radio frequency (RF) energy or another structurally disruptive energy provided by the probe. Optionally, the operations of blocks 112 and 111 occur at least partially simultaneously. In some embodiments, as energy delivery progresses, the tissue may be partially "plasticized," allowing for more movement due to mechanical deformation. In some embodiments, heating induced by the delivery of the structurally disruptive energy is also used to drive the induced mechanical deformation, for example, by using a probe containing a shape memory alloy that, when heated above its transition temperature, triggers the heating electrode to move.

[0090] Using the same element to mechanically deform and structurally disrupt tissue has the potential advantage of simplifying the device's structure and / or operation. In this case, at least one of the electrodes also acts as a piercing element, which in turn acts to stretch and / or compress the tissue and / or may be a jaw that is rotated to apply a torsion to the tissue.

[0091] However, the method of FIG. 1B does not necessarily require that the mechanical distortion of the tissue be performed by the same electrodes used to deliver the structural disruptive energy. For example, pliers operated through a catheter different from the catheter through which the structural disruptive energy is applied may be used to collect the tissue. In this case, the application of the structural disruptive energy may be performed using, for example, either a surface-contacting electrode or an electrode that penetrates (pierces) the tissue itself.

[0092] In some embodiments, the jaws of the tissue-deforming pliers are inserted into the tissue at a location outside the target zone of structural disruption and squeezed to deform the tissue, including the target zone itself, and then energy is applied to structurally disrupt the tissue within the target zone, which has the potential advantage of concentrating mechanical forces on tissue that remains healthy rather than potentially weakened by the application of structurally disruptive energy.

[0093] Reference is now made to Figure 2A, which schematically illustrates an electrical monopolar ablation system 90. Reference is also made to Figure 2B, which schematically illustrates a bipolar ablation system 91. Ablation systems of this general type are known for use in ablating cardiac tissue for the treatment of cardiac conditions such as atrial fibrillation.

[0094] The method of FIG. 1 is optionally performed using an RF ablation electrode as known in the art, for example, an RF ablation electrode configured as generally described in connection with FIGS. 2A-2B.

[0095] In some embodiments, the ablation system 90, 91 comprises an RF generator 71 configured to generate radio frequency (RF) energy used to perform ablation and to define parameters of the RF energy, e.g., its voltage and / or current, and / or the amplitude, frequency and / or pulse shape of the delivered RF energy.

[0096] The RF generator 71 is electrically connected (wired) to the ablation catheter 100. The ablation catheter 100 includes an ablation electrode 101, and ablative RF energy is delivered to the target tissue via electrical conductor 74 and grounded via an electrical interconnection with a conductive (e.g., metallic) ground electrode 72 (FIG. 2A) or secondary catheter electrode 101B (and conductor 75; FIG. 2B). The ground electrode 72 may be, for example, a plate placed under the patient while reclining during the medical procedure; or, for example, one or more conductive pads attached around the patient's arm / hand.

[0097] The RF system of Figures 2A-2B is described as an example of a device that can be used to perform annuloplasty. Ablation can be performed using alternatives, such as systems that induce tissue scarring via cryoablation, or thermal ablation using focused ultrasound. Optionally, the RF system of Figures 2A-2B is performed in a sub-ablative mode that destroys tissue structures without necessarily inducing cell death.

[0098] Reference is now made to Figures 3-5, which schematically illustrate a distal element of a steerable catheter 301 used to administer structurally disruptive energy (optionally an example of an RF ablation catheter 100, or an ablation catheter using another ablation energy type, e.g., a cryoablation catheter or a focused ultrasound ablation catheter), according to some embodiments of the present disclosure.

[0099] In some embodiments of the system used to perform the method of FIG. 1, catheter steering is provided to assist in guiding the energy delivery probe into contact with the portion of the annulus targeted for structural modification. It can be appreciated that the required steering angle may be acute, especially given the relatively limited space compared to the bulk of the target area. Furthermore, the steering angle can be selected so that the catheter preferably approaches the target surface area at a perpendicular or near-perpendicular angle. This can make it easier to establish a reliable contact surface and / or pressure that allows for the transfer of RF energy, while simultaneously reducing the tendency for the probe to "slip" along the target surface when the two meet at a more oblique angle. Additionally, the presence of a rigidity to the steering system steering that results in firm and reliable contact with the target tissue is a potential advantage.

[0100] 3-5 show elements of how a steering system having such features may optionally be provided in some embodiments of the present disclosure.

[0101] 3 shows a distal portion of outer tube 200 made, for example, from an electrically insulating material (e.g., PTFE, Pbax, or another electrically insulating material). Its distal tip 201 is pre-shaped to assume a relatively sharp bend, e.g., at least a 70°, 90°, 145°, or 180° bend, when unconstrained. Optionally, distal tip 201 comprises a spring element, such as a nitinol strip / element (completely encased inside the wall of outer tube 200), to increase its elasticity and / or mechanical stiffness properties.

[0102] Additionally or alternatively, the outer tube 200 includes an articulation mechanism, for example, an embedded puller wire that slides through a lumen inside the wall of the outer tube 200 and is rigidly connected to its tip, thus allowing the articulation angle to be controlled.

[0103] FIG. 4 illustrates an internal component 300. In the example of FIG. 4, the internal component 300 is used for RF delivery of structural disruptive energy. The illustrated example of the internal component 300 includes a metal / alloy conductive component 320 (e.g., made of stainless steel, nitinol, or another metal). The conductive component 320 is covered by an insulating layer 310 (e.g., made of PTFE, PEEK, polypropylene, polyamide, polyimide, Pbax, or another electrically insulating material), leaving exposed at least a distal exposed region 320A that acts as a transmission source of RF energy. Electrical interconnection (e.g., with an RF generator 71) is made via a connector 330. The internal component 300 is optionally structured for other energy types, such as a cryoablation catheter or a focused ultrasound ablation catheter. Other designs of the internal component 300 for use in RF disruption of tissue are described, for example, in connection with FIGS. 9-20 .

[0104] 5 shows a catheter 301 having an inner component 300 slidably disposed within an outer tube 200. When inner component 300 is connected to an RF generator (using connector 330), its distal tip can be activated, resulting in the destruction of a target location. Other inner component types may be connected to different sources of destructive energy and / or material, e.g., cryofluid in the case of a cryoablation catheter, or an ultrasound transducer control in the case of a focused ultrasound ablation catheter.

[0105] The material of the distal tip 201 is sufficiently rigid to allow the inner component 100 to deflect, yet sufficiently resilient and flexible to allow it to reversibly straighten itself, for example, upon sliding withdrawal into the guide catheter 302 (e.g., as shown in FIGS. 6-7). As the distal tip 201 is released from confinement (e.g., by advancement from the guide catheter 302), it resumes its pre-formed bend. In some embodiments, the curvature diameter of the distal tip 201 is 10-35 mm. In some embodiments, the curvature begins approximately 3-15 mm proximal to the tip.

[0106] Reference is now made to Figures 6-7, which schematically illustrate the manipulation of catheter 301 within a heart chamber (left atrium 50) in accordance with some embodiments of the present disclosure. Reference is also made to Figures 8A-8D, which schematically illustrate additional configurations of catheter 301, from among various that allow for the delivery of structural disruption energy to any location along the valve annulus.

[0107] 6 shows catheter 301 inserted into the left atrium through guide catheter 302 (positioned within the septum). Linear and rotational motion of outer tube 200 and linear motion of inner component 300 enable a physician to position energy delivery segment 602 (which may be, for example, conductive component 320) against target tissue (e.g., valve annulus or atrial / myocardial wall) and activate it to destroy tissue. In some embodiments (e.g., as described in connection with FIGS. 9, 14, and / or 18), a physician may also rotate / torque inner component 200 when inner component 200 has a spiral or drill-like tip shape that enables destruction within tissue.

[0108] The physician can then direct the energy delivery segment to another location on the annulus (as shown in Figure 7) to disrupt that structure.

[0109] By controlling / positioning the outer tube 200 and inner component 300, the physician can reach and disrupt any location along the valve annulus. Figures 8A-8C show the configuration of the catheter in other states without the sheath: For fully unsheathed ( FIG. 8A ), outer tube 200 is rotated, for example, a full 90°. Optionally, another fully unsheathed angle is configured, e.g., the example in FIG. 8D shows outer tube 200 bending through a full 180° when unsheathed from guide catheter 302. By bending outer tube 200, distal opening 202 of outer tube 200 is also reoriented to a new angle relative to the longitudinal axis of the distal portion of guide catheter 302. Partially unsheathed (FIG. 8B), allowing partial deflection of the outer tube 200 away from the longitudinal axis of the distal end of the guide catheter 302 (e.g., obliquely, but if the maximum bend angle is greater than 90°, the partial deflection can be a 90° deflection). · Fully sheathed or nearly fully sheathed so that the distal opening 202 remains oriented perpendicular to the longitudinal axis of the tip of the guide catheter 302 (FIG. 8C).

[0110] Reference is now made to Figures 9-20, which schematically illustrate alternative designs of inner component 300 for use with RF ablation systems, according to some embodiments of the present disclosure. In some embodiments, the designs of inner component 300 described in connection with Figures 9-20 are provided as alternative implementations of energy delivery electrode 100 in the systems of Figures 2A-2B.

[0111] 9-10 show at least an inner component 300 comprising one or more conductive components 320 attachable to RF power by respective connectors 330, 331. Over most of their length, the conductive components 320 are covered by an electrical insulator 310, optionally comprising one or more lumens of polymer tubing and / or an electrically insulating coating. The designs shown differ in details such as how the conductive components 320 terminate at their tips (which in each case are the electrodes through which RF energy is delivered), how many conductive components 320 are provided, and / or how they are arranged. In addition to the specific combinations shown, the illustrated features can be combined among different embodiments as long as they are compatible with each other; for example, different tip types (e.g., helical tip, conical tip, threaded tip, blunt tip, and rounded tip) can be provided in any combination on the conductive components 320 (e.g., monopolar, bipolar coaxial, and bipolar non-coaxial).

[0112] In FIG. 9, inner component 300 comprises a spiral tip 302 that is attachable to RF power by a monopolar connector 330 via a conductive component 320 .

[0113] Rotating the inner component 300 while advancing screws the spiral tip 302 into the target tissue (e.g., into the connective tissue of the valve annulus). This may be performed as a preliminary step to ensure stable contact and / or deeper scar penetration before disruption is performed by delivering RF energy through the spiral tip 302. Optionally, the spiral tip 302 is sharpened to facilitate entry into the target location (e.g., by engaging tissue and then rotating the inner component 300 relative to the outer tube 200).

[0114] Optionally, inner component 300 includes a distal surface 340 that limits the penetration depth of the energy delivery tip (e.g., tip 302 of FIG. 9) into the target tissue. Distal surface 340 is also shown in each of FIGS. 10-15 and 17-20, and serves the same depth-limiting function, at least for electrode tips that are intended to penetrate tissue to a certain depth.

[0115] FIG. 10 shows a schematic representation of a monopolar inner component 300 having a distal tip 305 that is sharp and capable of linear penetration into tissue.

[0116] FIG. 11 shows a schematic representation of a bipolar inner component 300 tipped with two electrodes 308 , 309 .

[0117] 12 shows a schematic representation of a bipolar inner component 300 having a tubular electrode 317 (which does not penetrate tissue) and a sharp-tipped, tissue-penetrating electrode 318. The tubular electrode 317 may comprise a solid wall, a helical structure, and / or a conductive mesh structure.

[0118] FIG. 13 schematically illustrates a bipolar inner component 300 having electrodes 315 and 316 that engage target tissue by end contacts of a conductive component 320 without penetrating the tissue.

[0119] 14 schematically illustrates a bipolar inner component 300 having a tubular electrode 304 that does not penetrate the target tissue and a distal spiral tip electrode 303 with a sharpened end that penetrates the target tissue. The tubular electrode 304 may have a solid wall, a spiral structure, and / or a conductive mesh structure.

[0120] FIG. 15 shows schematically a monopolar inner component 300 having a single conductive component 320 terminating in an electrode contact surface 321 flush with surface 340 .

[0121] FIG. 16 shows a schematic representation of a monopolar inner component 300 having a single conductive component 320 terminated distally in an atraumatic rounded segment 324 .

[0122] FIG. 17 shows a schematic representation of a bipolar inner component 300 having a pair of inner components 320 terminated distally in atraumatic rounded segments 327 .

[0123] 18 shows a schematic representation of a monopolar inner component 320 having an electrode with a distal threaded sharp tip 328. A spiral groove 329 potentially mitigates pre-activation penetration into the target tissue by rotation and perforation.

[0124] 19 schematically illustrates the inner component 300 together with the outer tube 200, allowing for various selectable penetration depths of the electrode tip 362A. The conductive component 320 can slide longitudinally against the distal surface 340 of the insulating tube 363 (the insulating tube 363 is an example of an insulating layer 310), and is optionally locked in place, for example, by a locking control element on the proximal side of the device. The slide allows for different penetration depths to be defined by adjusting the distance 1901 between the distal surface 340 and the most distal tip of the electrode 362A.

[0125] A potential advantage of this is that it allows the desired destruction depth to be varied for each location selected for energy delivery according to, for example, the depth of the annular connective tissue, the angle of approach to the tissue, and / or the proximity of structures that should not be destroyed, such as nearby coronary arteries.

[0126] FIG. 20 schematically illustrates an inner component 300 having a selectable depth, where the depth of penetration (distance 2002) is selected by adjusting the relative longitudinal position of the distal-most tip of electrode 362A to the distal surface 340 of the outer tube 200.

[0127] This configuration allows for tissue penetration beyond the uninsulated depth 2001 of the tip 362A while maintaining control of the penetration depth. The layer of tissue above the uninsulated depth 2001 of the tip 362A is potentially relatively free from damage during the delivery of structurally disruptive energy.

[0128] Optionally, any of the internal components 300 (e.g., of FIGS. 9-20 ) include one or more lumens operable as working channels, useful, for example, for translating a guidewire(s), injecting irrigation fluid, aspiration, and / or injecting radiopaque liquids. Thermocouple sensors are optionally provided on any of the internal components 300 at or near their tips and routed distally along the internal component to a connection with an external controller. This allows for monitoring, which has the potential advantage of allowing a physician to stop the delivery of energy once the tissue has heated to a certain threshold temperature. Optionally (using the controller), the destruction can be automatically stopped once the tissue reaches a certain threshold temperature.

[0129] Additionally or alternatively, tissue impedance is optionally measured via one or more electrodes used to deliver energy to track the progression of destruction. For example, a change in tissue impedance (typically, for example, an increase of about 7-fold) can be used to determine when ablation is complete or when a target intermediate state of tissue destruction has been reached.

[0130] The change is optionally used to automatically stop tissue destruction after a certain impedance threshold (e.g., a magnitude greater than about 2200 Ω) is reached and / or after a certain magnitude of impedance change occurs (e.g., an increase in impedance magnitude of about 1800 Ω to 1900 Ω, or an increase by a factor of 5, 6, 7, 8, or another factor). Impedance can be measured at an RF frequency, e.g., a frequency of about 500 kHz. Additionally or alternatively, impedance can be used to confirm initial penetration of the electrode into the tissue (e.g., a decrease in impedance, e.g., to about 400 Ω) and / or to confirm that the distance between the electrodes has closed to a smaller distance (e.g., a decrease in impedance magnitude, e.g., to about 100 Ω and / or to a value of about 300 Ω). Using electrodes that deliver structural disruption energy for measurement also has the potential advantage of eliminating the need for additional signal wiring to the device.

[0131] The impedance change values ​​given were observed in tissue using electrodes with a cross section of approximately 0.4 x 0.4 mm, a penetration depth of approximately 4 mm, and an RF frequency of approximately 500 kHz. Different values ​​may be observed using different electrodes and / or operating conditions.

[0132] Tissue remodeling by structural disruption of mechanically deformed tissue Reference is made to Figures 21A-21B, 22, 23, 24A-24B, and 25, which schematically illustrate methods for shaping tissue by delivering structural disruption energy while the tissue is mechanically deformed.

[0133] Cross-sectional view 21A and top view 21B show a scarred region 2100 resulting from activation of device 1000 (e.g., by delivery of RF energy) while positioned within tissue 2000. The destruction zone may be roughly characterized by a depth of destruction 2000 and a diameter of destruction 2101. While treated as cylindrical for purposes of illustration, it should be understood that the destruction zone is not necessarily cylindrical, and tissue and heat transfer are not necessarily uniform. The illustrated scenario is similar to that created by any of the embodiments of internal component 300 that include tissue-penetrating electrodes. After destruction, destruction zone 2100 tends to shrink (e.g., potentially as a result of fluid loss, cell death, and / or coagulation).

[0134] From the results of their in vivo and ex vivo experiments, the inventors have recognized additional effects that can be utilized to both fixate and / or contract (or shape) tissue, such as that of a heart valve annulus. Originally (before destruction) elastic tissue can be forced to undergo a certain amount of plastic deformation (in addition to that normally induced by its own contraction) by being subjected to mechanical deformation while administering fracture energy (more specifically, fracture energy that produces coagulation). In particular, the use of compression offers potential advantages for annuloplasty applications, for example, by enabling sufficient contraction around the valve using fewer applications and / or a smaller area of ​​tissue destruction.

[0135] 22-24B illustrate one method of producing plastic deformation by compressing tissue during lesion.

[0136] In FIG. 22, in some embodiments, electrode 1010 and electrode 1020 are inserted into tissue 2000 with a distance 2201 between them.

[0137] 23, the distance between the electrodes is reduced to a shorter distance 2202 while the electrodes remain within the tissue 2000. This creates a mechanical compression of the tissue between the electrodes 1010, 1020.

[0138] 24A and 24B illustrate the respective zones of destruction 2110 and 2120 for electrodes 1010, 1020 during their operation (e.g., transmission of RF energy) to destroy nearby tissue. Distance and energy delivery parameters are optionally selected such that zones 2110, 2120 share a common section 2200, resulting in a continuous zone of destruction.

[0139] Lesion can have the effect of destroying some of the tissue's elasticity (e.g., by lysing cells), while other effects tend to tighten and stiffen cellular and / or extracellular components (e.g., by denaturing proteins), so that they resist returning to their original shape. In effect, lesion locks the tissue into a new preferred configuration, which is more similar to the compressed shape used during lesioning than to the shape the tissue was previously processed into.

[0140] Upon release of the external force (e.g., relaxation of compression between electrodes 1010 and 1020), the tissue potentially adopts a new equilibrium state, e.g., a state in which distance 2203 between electrodes 1010, 1020 (FIG. 25) is less than distance 2201. Distance 2203 is typically greater than distance 2202, so long as some elastic memory of the original tissue shape remains. Removal of the electrodes leaves behind disrupted and compressively remodeled tissue.

[0141] If the electrodes overly compress the tissue between them (or overly stretch the tissue), there is a risk that structural breakdown of the tissue could result in cutting injury that could potentially negate the intended outcome.

[0142] Alternatively, if the level of applied energy (e.g., RF energy) is too low, the destruction zone may not extend into some of the most deformed areas (e.g., the destruction zone may not be continuous between electrodes). This can result in a reduced magnitude of the target effect. However, it is important to select an energy level that is safe and does not induce electrical harm (e.g., ventricular fibrillation) in the patient. In general, selecting lower power for a longer duration is safer (e.g., 10 watts for 12 seconds is safer than the same energy level alternative of delivering 30 watts for 4 seconds).

[0143] Effective potential settings and parameters for tissue destruction include inserting the tissue electrodes at an initial distance 2201 of about 4 mm, compressing the tissue between them until the distance between them is about 1.7 mm, and destroying the tissue structure with RF energy at 7 watts of power for 16 seconds. These parameters were derived through experimentation using electrodes having a width of 0.4 mm and with a tissue penetration of about 4 mm.

[0144] Note that each of the electrodes 1010, 1020 is shown in Figures 22-25 with a beveled tip 1021. This provides a lateral aspect to the electrode cutting surface. Orienting the beveled surface with the uncut (or less cut) side 1021A facing inward potentially reduces the risk of cutting compressed tissue.

[0145] Reference is now made to Figures 26 and 27A-27B, which schematically illustrate an electrode pliers 1100, according to some embodiments of the present disclosure.

[0146] A pincer 1100 may be provided at the distal tip of a flexible, low-profile catheter for use in disrupting tissue structures via an endovascular approach.

[0147] Pincer 1100 ( FIG. 26 ) in some embodiments comprises electrodes 1010, 1020, which in the illustrated example also act as the tissue grasping (grasping and squeezing) elements of pliers 1100. Additionally, electrodes 1010, 1020 are shaped to penetrate the tissue being grasped. Optionally, portions along the length of electrodes 1010, 1020 are insulated to allow selective destruction of tissue at specific depths, for example, as described in connection with FIG. 20 .

[0148] Typically, the cover 1130 is rigidly connected to the frame 1120. Figures 27A-27B show one cover 1130 removed from the pliers 1100, illustrating the internal workings of the pliers 1100.

[0149] In some embodiments, a rack-and-pinion arrangement (FIGS. 27A-27B) is used to actuate the electrodes. In the example shown, each electrode 1010, 1020 has a separate rack (linear gear) 1160 to which it is rigidly attached. The pinion 1150 may be a spur gear that rotates to move the rack and translate the electrodes toward or away from each other. The frame 1120 and cover 1130 are shaped to hold and guide these components, for example, to hold them in recesses 1121 and guide the movement of the electrodes along slots 1122.

[0150] The spur 1160 is rigidly connected to the elongated member 1140 (e.g., a rod or wire). Once the pliers' electrodes 1110, 1120 are implanted in tissue, the rotating elongated member 1140 rotates the pinion 1150 as the remainder of the body of the pliers 1100 is fixed. Additionally or alternatively, as described in connection with FIGS. 28A-28C , the elongated member 1140 may itself be housed within the tube 300, allowing electrode distance adjustment by rotation of the elongated member 1140 relative to the device casing, even when there is no external resistance to rotation.

[0151] In FIG. 27A, the electrodes 1020, 1010 are spaced at their widest distance, and in FIG. 27B, rotation of the pinion 1150 brings them closer together by meshing with the linear gear 1160. Whether the device results in tissue stretching or compression depends on how it is used. Penetration in the widely spaced configuration of FIG. 27A, followed by a decrease in inter-electrode distance (FIG. 27B), tends to compress the tissue. Penetration in the closely spaced configuration of FIG. 27B, followed by an increase in inter-electrode distance (FIG. 27A), tends to stretch the tissue.

[0152] In some embodiments, components of pliers 1100 are metallic and fabricated, for example, by laser cutting a flat stock to fabricate plates, gearing, and / or electrodes. In some embodiments, electrical insulation from the environment is provided by tip casing 1310, for example, as described in connection with FIGS. 28A-28C. Optionally, electrical insulation of one or more of covers 1130, frame 1120, and / or elongated member 1140 from the environment and / or from components that transmit RF energy is provided by coating the surfaces of these elements with an electrically insulating polymer (e.g., perylene-c or PTFE).

[0153] Optionally, the frame 1120 and cover 1130 are made entirely of an insulating material (e.g., a polymer). If the pinion 1150 itself is conductive, it may be used to transfer RF power to the electrodes 1010, 1020 via electrical conduction through their respective (conductive) linear gears. Alternatively, the electrodes 1010, 1020 may be directly connected to power leads. In this case, the pinion 1150 is optionally itself formed from a polymer, allowing the electrodes 1010, 1020 (if each has its own power lead) to operate in a bipolar mode rather than as two different parts of a monopolar electrode.

[0154] The combination of pliers and electrode functions within electrodes 1010, 1020 has potential advantages in simplifying device design and may also simplify device operation, however, it should be understood that these functions are optionally performed by separate components.

[0155] For example, grasping is optionally performed by pliers that are first manipulated to grasp and reshape (e.g., compress) the tissue (e.g., with or without initial penetration of the tissue). Once the tissue has been reshaped, an electrode may be placed on or inserted into the tissue and manipulated to disrupt it. This has the potential advantage by optionally separating the region of greatest injury energy from the region of greatest mechanical stress, potentially reducing the likelihood of tearing due to tissue weakening during or after structural disruption of the tissue.

[0156] Reference is now made to Figures 28A-28C, which schematically illustrate a coated catheter tip casing housing the features of Figures 27A-27C, according to some embodiments of the present disclosure. This can be used to sheathe the electrodes 1010, 1020, for example, during navigation of the catheter to the target tissue to avoid damage from the sharp tips of the electrodes. Once the electrodes 1010, 1020 are exposed, the distance can be adjusted as needed.

[0157] In some embodiments, the tip casing 1310 comprises a polymer (e.g., PEEK, PTFE, etc.) and / or a metal (e.g., stainless steel, titanium, and / or another biocompatible metal) with a polymer coating (e.g., perylene-c or PTFE).

[0158] As a result, the casing 1310 is electrically insulating (thus there is a small amount of electrical leakage to non-target tissue during application of structural disruptive energy). Additionally, in embodiments in which the tip 1310 is polymeric (and not radiopaque), the electrodes 1010, 1020 (which are metallic and relatively radiopaque) are well visualized under fluoroscopy. Optionally, the tip casing 1310 includes radiopaque markers to allow visualization of the positioning of the electrodes 1010, 1020 relative to the casing 130 (e.g., inside or outside the casing 1310) under fluoroscopy.

[0159] To assist with ultrasound visualization, the casing 1310 may include surface textures, such as grooves, that can enhance its echogenic properties. Optionally or additionally, a slow flow of fluid (e.g., saline) through the casing 1310 may be used to increase echogenicity and help localize the location of the casing 1310.

[0160] In the retracted configuration (e.g., used for navigation), the tip 1310 covers the electrodes (FIG. 28A). Once the tip of the casing 1310 is positioned against the target tissue, the electrodes 1010 are removed, for example, by advancing them out of the casing 1310 and / or pulling the casing 1310 back. For example, the tube 1300 is rigidly connected to the tip 1310, and by withdrawing it, the electrodes 1010, 1020 are exposed (FIG. 28B).

[0161] Once the electrodes 1010, 1020 are positioned inside the target tissue, the operator can reduce the distance between them (e.g., using the internal drive mechanism 1100 described in connection with Figures 27A-27C) as shown in Figure 28C. The device is activated, for example, using RF energy.

[0162] Other aspects of this configuration are as follows: In some embodiments, tube 1300 comprises a polymeric material (e.g., Pbax or PTFE). Optionally, the polymeric material is metal-reinforced (e.g., using a metal braid or helix) to support the necessary mechanical and electrical properties of the catheter (i.e., steerability / flexibility, rotatability / torque-ability, pushability, and electrical insulation).

[0163] In some embodiments, the casing 1310 includes a distal taper 1330 and a proximal taper 1340, potentially beneficial in supporting smooth back-and-forth movement of the catheter through the guide sheath (and / or body lumen). The casing 1310 includes a slit 1320 through which the electrodes 1010, 1020 can protrude when uncovered and slide along in response to remote actuation commands. The width of the slit 1310 matches the width of the electrodes 1010, 1020 (e.g., within a tolerance of approximately 0.1-0.2 mm around the electrodes, which themselves may be, for example, approximately 0.4 mm wide). The resulting small opening size may allow a minimal amount of blood to penetrate the tip. This potentially helps reduce leakage of electrical RF energy (such leakage is essentially noise that complicates the ability to control the application of structural disruptive energy in a repeatable, durable, and / or stable manner). In some embodiments, sealing is aided by sliding and / or elastic gaskets provided inside the slits 1320 through which the electrodes 1010, 1020 enter when unshrouded.

[0164] The casing 1310 provides another potential advantage by preventing inadvertent penetration of the electrodes 1010, 1020 into the valve leaflets or other non-target tissue while the casing 1310 is being moved within the body. For example, the electrodes 1010, 1020 are extended directly into the tissue after verifying (e.g., using transesophageal or intracardiac echocardiography) that the casing 1310 is positioned relative to the annular tissue targeted for remodeling. After the tissue structure is disrupted, the electrodes 1010, 1020 are retracted within the casing 1310 before being moved again (e.g., moved to a new treatment position or withdrawn from the body). Optionally, the distance between the electrodes 1010, 1020 is reset to a wide position after being withdrawn from the tissue and while they are retracted within the casing 1310.

[0165] Reference is now made to FIG. 29, which schematically illustrates the positioning via an endovascular approach of a distal portion of a catheter used for annuloplasty of a mitral valve 48, according to some embodiments of the present disclosure.

[0166] In some embodiments, a transseptal guide catheter 302 is guided via the inferior vena cava 45 to the right atrium 46. The guide catheter 302 is guided to enter the interatrial septum 46 (preferably via the fossa ovalis) to gain minimally invasive access to the left atrium 44. A catheter including the outer tube 200 (including the energy delivery element 1310) and the inner component 300 is inserted through the guide catheter 302 into the left atrium 44. Alternatively, in some embodiments, access to the heart is via the superior vena cava 43, which is potentially advantageous for treatments targeting the tricuspid valve annulus.

[0167] Optionally or alternatively, the guide catheter 302 itself includes a distal steering section (instead of a curved pre-shaped form) and / or the sleeve 1400 has a curved pre-shaped distal segment (instead of the steering segment described above).

[0168] The controllable degrees of freedom of outer tube 300 include rotation R 1 relative to guide catheter 302 and longitudinal advance / retraction E 1 relative to guide sheath 1500 .

[0169] In some embodiments, the outer tube 300 also comprises a steering segment S that bends through a range of angles, e.g., by active steering (e.g., controlled by shortening control wires) and / or via a pre-formed curved shape uncovered, e.g., as described in connection with Figures 3-8D. In some embodiments, steering is performed by a steering mechanism provided to guide the catheter 302 itself.

[0170] The controllable degrees of freedom of the inner component 300 include linear translation E2 relative to the sleeve 302 and rotation R1 relative to the sleeve outer tube 200. In combination, the controllable degrees of freedom allow the catheter tip 1310 to be positioned at a selected position, orientation, and angle along the valve annulus, from which electrodes can be deployed to penetrate the annulus and perform structural disruption of the tissue.

[0171] 30 shows the optional proximal side of the catheter (positioned outside the patient's body). The outer tube 300 is inserted into the guide catheter 302 and includes a handle 1450 that is used to control longitudinal advancement and steering (angulation) of its distal segment relative to the guide catheter 302.

[0172] The inner component 300 is then positioned inside the outer tube 200. The handle 1350 controls the longitudinal advancement and rotation of the inner component 300 relative to the outer tube 200.

[0173] In some embodiments, the handle 1260 drives deployment of the electrodes 1020, 1020 by moving longitudinally relative to the tip casing 1310, for example, via connection with the tube 1250, which in turn connects distally to the tube 1300. Rotation of the handle 1180 rotates the elongate member 1140 to drive the electrodes 1010, 1020 laterally, for example, as described in connection with Figures 26-27B.

[0174] Additionally, the handle 1260 (or the handle 1180) includes a hole through which an electrical cable 1710 passes, allowing connection of the electrodes 1010, 1020 and the RF generator 1700.

[0175] Reference is now made to Figures 31A-31E, which schematically illustrate different constructed layers of an adjustable width catheter, according to some embodiments of the present disclosure. In the cross section depicted in Figure 31A, wire 1140 is shown rigidly connected at its proximal side to the distal side of tube / shaft 1170. The rigid connection may be made, for example, by crimping tube 1170 onto wire 1140, by gluing them together, and / or by welding them together using laser cutting techniques.

[0176] In some embodiments, the tube 1170 is constructed from a metal (e.g., stainless steel or nitinol) and includes a flexible segment 1175. The segment 1175 can be made flexible, for example, by laser cutouts (e.g., slits or an interlocking pattern, e.g., as described in connection with FIG. 32) in a walled tube. Alternatively, the segment 1175 may be made flexible by construction from a metal braid and / or one or more wire helices. In some embodiments, the metal braid and / or wire helices reinforce a polymeric tube (e.g., PEEK, polyimide, PTFE, and / or Pbax).

[0177] 31B shows the next outer layer. Tube 1200 is assembled onto tube (or shaft) 1170 and rigidly connected (e.g., using laser welding) to cover 1130. Rotating tube / shaft 1170 relative to tube 1200 drives electrodes 1010, 1020 laterally, bringing them closer together or moving them apart. Tube 1200 includes flexible segment 1210, fabricated, for example, as described for flexible segment 1175.

[0178] At least one of the tubes or shafts 1170, 1200 is metallic and allows for the conduction of electrical energy along the catheter to the electrodes 1010 and 1020 (eg, via the proximal cover 1130).

[0179] 31C shows an insulating sleeve 1250 assembled and tightly connected over the tube 1200. The sleeve 1250 is made of a polymer (e.g., PTFE or polyolefin) to electrically insulate the conductive inner tube. In some embodiments, the sleeve 1250 is heat shrink tubing, which has the potential advantage of simplifying the assembly process.

[0180] Tube 1300 (FIG. 31D) is assembled onto sleeve 1250 and tightly connected (e.g., using adhesive) to tip casing 1310. Tube 1300 can be slid forward / backward over sleeve 1250, allowing electrodes 1010, 1020 to be covered or exposed.

[0181] In some embodiments, outer tube 200 (FIG. 31E) is in turn assembled onto tube 1300. Tube 1300 can be advanced / retracted / rotated relative to outer tube 200. In some embodiments, the distal tip of sleeve 200 includes a steering segment to allow it to bend to support the movements and configurations described in connection with FIG. 29, for example.

[0182] Reference is now made to FIG. 32, which shows an exploded view of a self-locking pattern 3200 cut to provide flexibility to tube 1170 and / or tube 1200, according to some embodiments of the present disclosure. The cuts (preferably manufactured using laser cutting techniques) create a series of separate but geometrically connected links. Individual links allow for slight movement, while collective links allow for larger angular bends. The cuts are made using linking elements 3201, 3202 to prevent the tubes from separating. As a result, the tubes support a high level of maneuverability (i.e., the ability to pass through geometries with small radii of curvature while having good push and pull capabilities) while retaining a high level of torque capacity (needed to transmit torque along the tube that drives the electrodes laterally).

[0183] Torsional contraction Reference is now made to FIG. 33 , which schematically illustrates an electrode configuration that inserts into tissue, twists, and then disrupts its structure, according to some embodiments of the present disclosure. Inner component 1900 is an example of inner component 300 that includes a single electrode 1910 protruding from an insulating sleeve 1901 that itself fits within outer tube 200. The electrode 1910 is shaped so that when inserted into tissue and twisted, it drags the surrounding tissue along. The amount of twist may be, for example, about 45°, 90°, 135°, or another distance. However, the twist should remain below a level of force that would induce the tissue to return to its untwisted state.

[0184] In some embodiments, this is achieved using a circumferential shape that extends radially farther from the electrode's central axis in some locations compared to other locations on the periphery that are closer to the radius. This creates a tissue surface that the electrode presses against (rather than simply passing through) as it rotates, creating a twist in the surrounding tissue. A simple example of such a periphery is a rectangular cross-sectional shape. Triangular wave and cross-sectional shapes provide alternative examples. Additionally or alternatively, the electrode (or electrodes) may comprise multiple, separated shapes that are inserted into the tissue, such as two, three, four, or more spikes, flat blades (e.g., oriented radially from a common center), or other shapes. A larger total surface area is potentially preferable, reducing the buildup of focal stresses that increase the risk of tissue tearing.

[0185] Reference is now made to Figures 34A-34D, which illustrate a method of twisting and disrupting perivalvular reduction, according to some embodiments of the present disclosure.

[0186] Figure 34A shows a cross section of an electrode 1910 inserted into a block of tissue 2000. Figure 34B shows the same scenario from a perspective looking down on the surface 2001 of tissue 2000. Distance 3401 represents the initial distance between two points 3402, 3403 placed along the circumference of the annulus tissue to be adjusted.

[0187] 34C, the electrode 1910 is twisted, resulting in torsional tissue movement indicated by the arrows leading between points 3402 and 3402A, and between points 3403 and 3403A. Incompressible tissue volume may shunt into a tissue bulge (e.g., into an open area adjacent to tissue 2000) in response to stress. This potentially shortens the overall circumference as it "winds up," including pulling in tissue portions at points 3402A, 3402B, and pulling tissue portions somewhat closer together than they were previously at points 3402, 3403.

[0188] FIG. 34D shows the situation after disruption of region 2100 and removal of electrode 1910. The tissue at points 3402A and 3403A partially relaxes back to points 3402B and 3403B, but does not fully relax back to its original position due to plastic deformation as a result of scarring. Tissue contraction further reduces the direct distance (e.g., distance 3406 is shorter than distance 3405). In the direction of the valve circumference, points 3402B and 3403B are separated by distance 3407, which is even shorter. The difference between distances 3407 and 3401 is somewhat greater than the overall reduction in perimeter because some of the twisted tissue volume has been redirected laterally outward by twisting, even as other tissue is pulled laterally inward. Nevertheless, there may be an overall combined effect of perimeter shortening due to the "set" of both tissue contraction and tissue plastic remodeling while the tissue is held in the twisted configuration.

[0189] For example, it should be noted that the pinching-type compression described in connection with Figures 21A-25 is optionally implemented in conjunction with the torsional compression described in connection with Figures 33-34D, potentially increasing the amount and / or extent of circumferential contraction that can be elicited from a particular site of disruptive energy delivery.

[0190] Reference is now made to FIGS. 35A-35B, which schematically illustrate the configuration of an electrode assembly comprising two needle electrodes 1010, 1020 interconnected by a loop spring 1600, according to some embodiments of the present disclosure.

[0191] The electrodes 1010, 1020 are connected to opposite sides of a loop spring 1600, which itself comprises a shape memory alloy such as Nitinol. The loop spring 1600 is used as the actuator for the device. Optionally, another actuator comprising a shape memory alloy is used, for example, a separate leaf spring or coil spring.

[0192] Above the transition temperature of this alloy, the loop spring 1600 relaxes, pulling the electrodes 1010, 1020 closer together (FIG. 35B), i.e., "normally closed." When the loop spring 1600 is held in an open (open) position, the electrodes 1010, 1020 are separated. This element is optionally used in place of, for example, the rack and pinion mechanism described in connection with FIGS. 26-27B.

[0193] In some embodiments, the shape memory alloy used is set to a transition temperature above body temperature, for example, in the range of 37°C to 60°C. This results in the loop spring 1600 being "soft" prior to use. The loop spring 1600 begins to cool below the transition temperature and is bent into an open state. Due to the properties of the shape memory alloy, the shape memory alloy remains in that state until heated. The electrode can be inserted into tissue in this configuration and then manipulated to perform tissue disruption.

[0194] During operation, the electrodes heat up, causing the heating loop spring 1600 to exceed its transition temperature. Additionally or alternatively, the loop spring 1600 self-heats due to electrical resistance to current flowing through it. Heating causes the electrodes to collapse toward a closed state, drawing them together. This is another method of applying an external force to affect a plastic deformation effect in tissue, as described, for example, in connection with FIGS. 21A-25.

[0195] Reference is now made to Figures 36A-36E, which schematically illustrate the configuration of a mechanically actuated electrode assembly comprising two needle electrodes 1010, 1020 interconnected by a loop spring 1600, according to some embodiments of the present disclosure.

[0196] Regardless of the transition temperature of the material of the loop spring 1600, the loop spring 1600 can also be opened by mechanical force.

[0197] 36A shows elements of such a mechanism, which operates by the movement of a wedge 1610 to force open an opening in the loop spring 1600. The mechanism comprises two side plates 1615 on either side of the wedge 1610. The side plates 1615 are coupled to either side of the loop spring 1600 so that when they are separated, the opening in the loop spring 1600 also opens, causing lateral separation of the electrodes 1010, 1020.

[0198] With the wedge 1610 in its retracted position (FIG. 36A), the side plate 1615 is free to be pulled into its laterally folded state by the normally closed loop spring 1600. To the elements of FIGS. 36A and 36B, a cover plate 1630 is added, which helps to keep the wedge 1610 aligned with the side plate 1615. FIG. 36C adds a shaft 1190 that is rigidly attached to the wedge 1610. FIG. 36D adds an outer tube 1290, with cutouts showing internal details such as how the plates 1620 are positioned within the outer tube 1290 (to which they are rigidly attached). The shaft 1190 can translate longitudinally through the outer tube 1290, moving the wedge 1610 longitudinally.

[0199] FIG. 36E shows the same view as FIG. 36D, without the cutouts, and with the addition of an end cover 1295 with slots 1296 along which the electrodes 1010, 1020 move as they are displaced by the openings in the loop spring 600.

[0200] Reference is now made to Figures 37A-37C, which schematically illustrate operation of the mechanically actuated electrode assembly of Figures 36A-36E, in accordance with some embodiments of the present disclosure. In each of these figures, the view of the outer tube 1290 is suppressed along with one of the cover plates 1620.

[0201] 37A and 37B, it can be seen that plate 1615 slides freely as loop 1600 transitions between the collapsed and open configurations, which can occur, for example, as a result of a temperature-induced phase transition, as described in connection with FIGS.

[0202] 37C shows the wedge 1610 in a longitudinally advanced position, separating the plates 1615. This in turn forces the loop spring 1600 into its open position, with the electrodes 1610, 1620 laterally separated by a wider distance than when the spring 1600 is in its closed position.

[0203] This can be understood as a "reset" mechanism that allows loop 1600 to return to its open state again after it has cooled below its transition temperature. Once the device has been reset, wedge 1610 can be retracted again. Loop spring 1600 will remain in its open position until it is heated again. This has the potential advantage of allowing actuation of shaft 1190 as a momentary "push button" switch, which can instantly spring back to the configuration of FIG. 37A, resetting loop spring 1600.

[0204] Alternatively, the device of Figures 36A-37C can include loop spring 1600 made of a superelastic material that has a transition temperature below body temperature (e.g., below 37°C). This allows it to remain fully elastic at all times. In such an embodiment, the opening and closing of loop spring 1600 is set by the position of wedge 1610 relative to plate 1615, regardless of operating temperature.

[0205] general When used herein in reference to an amount or numerical value, the term "about" means "within ±10%."

[0206] The words "comprises," "comprising," "includes," "including," "having," and combinations thereof, mean including but not limited to.

[0207] "Consisting of" means "including and limited to."

[0208] The term "consisting essentially of" means that a composition, method, or structure may include additional ingredients, steps, and / or components, but only if the additional ingredients, steps, and / or components do not materially alter the basic and novel characteristics of the claimed composition, method, or structure.

[0209] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" can include a plurality of compounds, including mixtures thereof.

[0210] The words "example" and "exemplary" are used herein to mean "serving as an example, instance, or illustration." Any embodiment described as an "example" or "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments and / or to exclude the incorporation of features from other embodiments.

[0211] The term "optionally" is used herein to mean "provided in some embodiments and not provided in other embodiments." Any particular embodiment of the present disclosure may include multiple "optional" features, except where such features contradict each other.

[0212] As used herein, the term "method" refers to ways, means, techniques, and procedures for accomplishing a given task, including, but not limited to, methods, means, techniques, and procedures known or readily developed from known methods, means, techniques, and procedures by practitioners in the fields of chemistry, pharmacology, biology, biochemistry, and medicine.

[0213] As used herein, the term "treating" includes arresting, substantially inhibiting, slowing, or reversing the progression of a condition, substantially ameliorating the clinical or cosmetic symptoms of a condition, or substantially preventing the appearance of clinical or cosmetic symptoms of a condition.

[0214] Throughout this application, various embodiments of the present invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the present invention. Accordingly, the description of a range should be considered to have specifically disclosed not only each individual numerical value within that range, but also all possible subranges. For example, description of a range such as 1 to 6 should be considered to have specifically disclosed subranges such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, 3 to 6, etc., as well as each individual numerical value within that range, e.g., 1, 2, 3, 4, 5, 6, etc. This applies regardless of the breadth of the range.

[0215] Whenever a numerical range is given herein (e.g., "10-15," "10-15," or any pair of numbers linked by another such range designator), it is meant to include any numerical value (decimal or integer) recited within the given range, unless the context clearly dictates otherwise. The expressions "ranging from / between" a first and second designator number and "ranging from / between" a first designator number to a second designator number are used interchangeably herein and are meant to include the first and second designator numbers and all decimals and integers therebetween.

[0216] While the description of this disclosure has been provided in conjunction with specific embodiments, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the present invention is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims.

[0217] Certain features of the invention that are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment, and conversely, various features of the invention that are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable subcombination or in other described embodiments of the invention, as appropriate. Certain features described in the context of various embodiments are not considered essential features of those embodiments, unless the embodiment is inoperable without those elements.

[0218] All publications, patents, and patent applications mentioned in this specification are incorporated by reference in their entirety to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. Furthermore, citation or identification of any document in this specification should not be construed as an admission that such document is available as prior art to the present invention. To the extent section headings are used, they should not be construed as necessarily limiting. Additionally, the priority documents of this application are incorporated by reference in their entirety.

Claims

1. 1. A device for annuloplasty treatment, comprising: a catheter that is inserted transvascularly into a cardiac chamber through a percutaneous incision and has a size that allows it to reach the cardiac valve annulus; at least one tissue-piercing element at the distal end of the catheter; a rotary motion mechanism extending from the proximal end of the catheter to the distal end of the catheter, the rotary motion mechanism coupled to the at least one tissue-piercing element; the at least one tissue-penetrating element moves relative to the body of the catheter and acts to deliver tissue-disrupting energy to penetrate tissue of the heart valve annulus; The device, wherein the at least one tissue-piercing element has a non-circular cross-section that engages and induces a twist in tissue into which it is inserted when subjected to torque applied through the catheter by the rotary motion mechanism.

2. The device of claim 1 , wherein the at least one tissue-piercing element comprises a plurality of piercing elements that are adjustable in their relative distance while inserted into the tissue of the heart valve annulus.

3. 10. The device of claim 1, wherein each of the at least one tissue-penetrating elements is an electrode electrically interconnected to a connection that remains outside the percutaneous incision when the catheter is inserted into the heart chamber.

4. The device of claim 2 , wherein each of the plurality of piercing elements operates as an ablation electrode.

5. The device of claim 2 , wherein the plurality of piercing elements are inserted into the tissue at a relatively wide distance and spaced apart to adjust to a narrower distance.

6. The apparatus of claim 2 , wherein the relative distance of the plurality of piercing elements is adjusted by rotation of a gear.

7. The device of claim 6 , wherein the gear is rotated by a control element leading to a proximal side of the catheter.

8. 8. The device of claim 7, wherein the control element also acts to provide an electrical interconnection between at least one of the at least one tissue-piercing element and a power source that remains outside the percutaneous incision.

9. The device of claim 2 , wherein the relative distance of the plurality of piercing elements is adjusted by temperature changes of an actuator comprising a shape memory alloy.

10. The device of claim 9 , wherein the shape memory alloy is arranged such that the temperature change is induced by heating as a result of the plurality of piercing elements operating as electrodes.

11. 10. The device of claim 9, wherein the shape memory alloy is shaped to cause the plurality of piercing elements to move from an initial distance to a relatively small distance when heated.

12. 10. The device of claim 9, comprising a device reset operable to restore the distance of the plurality of piercing elements to before the temperature change while the device remains inserted into the heart chamber.

13. The device of claim 1 , wherein the non-circular cross section comprises a rectangular blade.

14. The device of claim 1 , wherein the non-circular cross-section has a shape with three or more blades extending radially from a central axis.

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