CENTERING STABILIZER FOR HEART VALVE DEVICE
FIELD OF THE INVENTION
[0001] The present invention generally relates to devices and methods for treating heart valves, such as but not limited to, aortic or tricuspid valve leaflets, and particularly to a stabilizer device that centers itself with respect to heart valve anatomy, such as the commissures.
BACKGROUND OF THE INVENTION
[0002] In many procedures in treating heart valves it is necessary to center a surgical device with respect to heart valve anatomy, such as the commissures.
[0003] For example, commissural alignment during transcatheter aortic valve replacement (TAVR) may be important to prevent complications, such as coronary occlusion. The TAVR heart replacement valve (or TAVR device for short) has its own commissures, referred to as neo-commissures. Improper alignment of the TAVR device may result in the neo-commissures overlapping the coronary orifices.
[0004] Similarly, the TAVR device is formed with commissural posts. If one of the commissural posts of the TAVR device lands in front of a coronary ostium, reaccess to the coronary artery can be very difficult. The extent of the coronary orifice overlap or coronary ostium blockage may lead to coronary occlusion and a need for TAVR-in- 1'AVR. With more and more TAVR procedures being performed on younger and lower risk populations with a longer life expectancy, the need for proper positioning of the TAVR device is critical.
[0005] Centering a TAVR device with respect to the commissures is challenging because the commissures are not spaced at perfectly identical angles from each other and the anatomy changes from one patient to another.
SUMMARY
[0006] The present invention seeks to provide a stabilizer device that centers itself with respect to heart valve anatomy, such as the commissures. The stabilizer centering device may be used in a variety of procedures, such as TAVR procedures and others. The stabilizer device may be used with a leaflet modification device or with a device that modifies other portions of the heart valve, such as but not limited to, the annulus, cusps, chordae tendineae, or portions of the extracellular matrix (EC’M) and valve interstitial cells (VIC), such as the elastin-, proteoglycan- and collagen-rich layers of the ECM.
[0007] For example, without limitation, the stabilizer centering device may be used, and is described herein, together with a leaflet modification device, such as a device for splitting or cutting valve leaflets, or for scoring calcifications in valve leaflets, such as aortic valve leaflets, in order to increase leaflet pliability and mobility, thereby increasing the cross-sectional area of the open valve in patients with aortic stenosis. In addition, the devices and methods described can be applied as a preparation step for trans-catheter aortic valve implantation, in order to allow valve implantation in heavily calcified or asymmetrically calcified native valves, to increase the cross-sectional area of the implanted valve and to decrease the risk of paravalvular leaks. The devices and methods may also be used for splitting leaflets or for scoring calcifications in other valves, such as the mitral valve.
[0008] The term “score” refers to any kind of reduction in size or any modification in shape or form, such as but not limited to, scoring, fracturing, pulverizing, breaking, grinding, chopping, cutting and the like, and the terms are used interchangeably.
[0009] There is thus provided in accordance with a non-limiting embodiment of the invention a heart valve treatment apparatus including a centering stabilizer comprising two or more struts, wherein the centering stabilizer is mounted on a catheter and fully rotatable about a longitudinal axis of the catheter, and a heart valve treatment device mounted on the catheter and rotatable about the longitudinal axis of the catheter, and the centering stabilizer is configured to center the heart valve treatment device with respect to a heart valve anatomical structure of a native or an artificial valve.
[0010] In accordance with a non-limiting embodiment of the invention the heart valve treatment device includes a housing formed with an elongate opening, wherein first and second ends of the housing are open so that the housing is rotatable about a longitudinal axis of a catheter that can pass through the first and second ends, an anvil arm and an anvil-support arm pivotally coupled to the anvil arm at a pivot, the anvil arm being pivotally coupled to the housing at a pivot and the anvil-support arm being pivotally coupled to a track link, which is arranged to travel along a track in the housing, wherein the anvil arm and the anvil-support arm are deployable radially outwards, a scoring element pivotally coupled to the housing at a pivot, the scoring element including scoring members, and a centering stabilizer including two or more struts, first and second ends of each of the struts being flexibly coupled to the first and second ends, respectively, of the housing, wherein the centering stabilizer is rotatable about the longitudinal axis of the catheter
BRIEF DESCRIPTION OF DRAWINGS
[0011] The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
[0012] Figs. 1A and IB are simplified perspective and side-view illustrations of a stabilizer centering device (also referred to as centering stabilizer) used with a heart valve treatment device, in accordance with a non-limiting embodiment of the present invention, in a contracted position suitable for being disposed in a delivery sheath.
[0013] Figs. 2A and 2B are simplified perspective and side-view illustrations of the heart valve treatment device, with a scoring element in a deployed position.
[0014] Figs. 3 A and 3B are simplified perspective and side-view illustrations of the heart valve treatment device, with an anvil arm and an anvil-support arm in a deployed position for scoring a leaflet positioned between the scoring element and the anvil arm.
[0015] Figs. 4A and 4B are simplified perspective and side-view illustrations of the heart valve treatment device delivered to the site of a heart valve (such as the aortic valve), in accordance with a non-limiting embodiment of the present invention, in which the device is in a contracted position suitable, and the device and the centering stabilizer have been unsheathed from a delivery sheath (not shown).
[0016] Figs. 5 A and 5B are simplified perspective and side-view illustrations of the heart valve treatment device positioned in the heart valve with the centering stabilizer registered with valve structure, typically the commissures, to center the device in the valve.
[0017] Figs. 6 A and 6B are simplified perspective and side-view illustrations of the heart valve treatment device with the scoring element deployed outwards.
[0018] Figs. 7 A and 7B are simplified perspective and side-view illustrations of the heart valve treatment device moved towards the leaflets of the valve so that the device has “landed” in the center of the valve and the scoring element is positioned on one side of one of the leaflets.
[0019] Figs. 8 A and 8B are simplified perspective and side-view illustrations of the heart valve treatment device, in which the anvil arm and anvil-support arm have been deployed to position on the other side of the leaflet, so that the leaflet is sandwiched between the scoring element and the anvil arm and the force of the anvil arm on the leaflet causes the scoring element to score the other side of the leaflet.
[0020] Figs. 9A and 9B are simplified perspective and side-view illustrations of the heart valve treatment device, in which the scoring element and the assembly of the anvil arm and the anvil-support arm have been rotated to a new position, either a new position on the leaflet itself or to a new position on the base of the leaflet to score other calcifications present in the valve.
[0021] Figs. 10A and 10B are simplified perspective and side-view illustrations of the heart valve treatment device, in which the device has been retracted (“un-landed”), for example, by a 20 mm movement in the retraction direction, so the device can either be removed or repositioned for transition between cusps.
[0022] Figs. 11A and 11B are simplified perspective and side-view illustrations of the heart valve treatment device showing partial contraction of the scoring element for movement (rotation and/or translation) inside of the centering stabilizer.
DETAILED DESCRIPTION
[0023] Reference is now made to Figs. 1A-3B, which illustrate a heart valve treatment device 10, in accordance with a non-limiting embodiment of the present invention.
[0024] The heart valve treatment device 10 may include a (e.g., slender, cylindrical) housing 12 formed with an elongate opening 14, which may have rounded ends. The housing 12 may be made of medical grade stainless steel or any other suitable material. A first end 16 and a second end 18 of housing 12 may be open so that device 10 can be mounted on a delivery catheter 20 (which could be a guidewire) that passes through housing 12. The first and second ends 16 and 18 can rotate freely about the longitudinal axis of catheter 20. The open ends of housing 12 also allow passage therethrough of actuator wires (not shown), which may be coupled to a proximal manipulator (not shown) for manipulating the actuator wires. [0025] As seen best in Figs. 3A and 3B, heart valve treatment device 10 may include an anvil arm 22 and an anvil-support arm 24 pivotally coupled to anvil arm 22 at a pivot 25. Anvil arm 22 may be pivotally coupled to an inner portion of housing 12 at a pivot 26. The anvil-support arm 24 may be pivotally coupled to a track link 28 at a pivot 29, which is arranged to travel along a track 30 in housing 12 (Fig. 3B). The track link 28 may be pulled towards the second end 18 of housing 12 by means of one of the actuator wires (not shown) that is coupled to the proximal manipulator (not shown). By pulling track link 28 towards the second end 18 of housing 12, the anvil-support arm 24 deploys radially outwards to the position shown in Figs. 3 A and 3B. Since anvil-support arm 24 is pivotally coupled to anvil arm 22, this motion causes anvil arm 22 to deploy radially outwards to the position shown in Figs. 3A and 3B (anvil-support arm 24 is at an acute angle with respect to housing 12 and anvil arm 22 is at an obtuse angle with respect to housing 12).
[0026] The heart valve treatment device 10 may include a valve treatment element 32, such as but not limited to, a scoring element 32, pivotally coupled to an inner portion of housing 12 at a pivot 33. (The valve treatment element 32 is described in the following description as scoring element 32, but the invention is not limited to scoring.) Scoring element 32 may include scoring members 34, such as but not limited to, comb-like teeth, dull teeth, sharp teeth, roughened edges or surfaces, knurled surfaces and others. As seen in Fig. 3B, anvil arm 22 may have scoring force bearing members 27, such as but not limited to, hardened or roughened surfaces, which bear the force applied against anvil arm 22 by the scoring action of scoring element 32.
[0027] Heart valve treatment device 10 may cooperate with a centering stabilizer 36, which may be constructed of two or more struts 38 (in the illustrated embodiment there are three struts 38), which may be made of a flexible material, such as but not limited to, nitinol or stainless steel. First and second ends 40 and 42 of each strut 38 are flexibly coupled to first and second ends 16 and 18, respectively, of housing 12. In the nonlimiting, illustrated embodiment, each strut 38 has a relatively narrow portion 44 coupled by a joint 45 to a relatively wide portion 46; the joint 45 may be closer to the second end 42 than to the first end 40. Joint 45 may a living hinge, for example. [0028] The centering stabilizer 36 can rotate freely about the longitudinal axis of catheter 20. The ability of centering stabilizer 36 to rotate freely about the longitudinal axis is not affected by coupling the centering stabilizer 36 to the heart valve treatment device 10. The reason is that the first and second ends 16 and 18 of housing can rotate freely about the longitudinal axis of catheter 20; the centering stabilizer 36 is coupled to ends 16 and 18, so therefore it can also rotate freely about the longitudinal axis of catheter 20. Thus, the centering stabilizer 36 and the heart valve treatment device 10 can rotate about the longitudinal axis of catheter 20 either together, or alternatively if not coupled, independently of each other.
[0029] In one embodiment, strut 38 (including relatively narrow portion 44, joint 45, and relatively wide portion 46) is sufficiently flexible such that they can deform to match, or to compensate for, the particular imperfect anatomy of any patient’s heart valve. This can significantly aid in proper alignment and reduce or eliminate coronary orifice overlap or coronary ostium blockage.
[0030] Reference is now made to Figs. 4A and 4B, which illustrate the heart valve treatment device 10 delivered to the site of a heart valve (such as the aortic valve), in accordance with a non-limiting embodiment of the present invention.
[0031] The aortic valve has three leaflets, or cusps: the left coronary cusp (LCC), the right coronary cusp (RCC), and the non-coronary cusp (NCC). The commissure CM is the anatomical structure where adjacent cusps abut against each other and are joined to each other. The term commissure also includes a portion of a wall or a portion of a tissue of an aortic wall in the vicinity of where adjacent cusps abut against each other.
[0032] In one method of using the device, device 10 may be percutaneously introduced through vasculature to the desired site over a delivery system (e.g., in which the device is initially sheathed and delivered over a guidewire and then unsheathed).
[0033] Reference is now made to Figs. 5A and 5B. Heart valve treatment device 10 is positioned in the heart valve with the centering stabilizer 36 registered with valve structure, typically the commissures, to center the device in the valve. This is due to the fact that centering stabilizer 36 can rotate freely about the longitudinal axis of catheter 20. The naturally closing and opening of the aortic valve, causes the struts 38 to rotate and land in the commissures. [0034] Reference is now made to Figs. 6A and 6B, which illustrate heart valve treatment device 10 with the scoring element 32 deployed outwards (by suitable manipulation of the actuator wire (not shown) connected to the proximal manipulator (not shown).
[0035] Reference is now made to Figs. 7A and 7B. Heart valve treatment device 10 has been moved towards the leaflets of the valve so that the device has “landed” in the center of the valve and scoring element 32 is positioned on one side of one of the leaflets.
[0036] Reference is now made to Figs. 8A and 8B. Anvil arm 22 and anvil-support arm 24 have been deployed to position on the other side of the leaflet, so that the leaflet is sandwiched between the scoring element 32 and the anvil arm 22. The force of the anvil arm 22 on the leaflet causes scoring element 32 to score the other side of the leaflet.
[0037] Reference is now made to Figs. 9A and 9B. The scoring element 32 and the assembly of the anvil arm 22 and the anvil-support arm 24 have been rotated to a new position, either a new position on the leaflet itself or to a new position on the base of the leaflet to score other calcifications present in the valve.
[0038] Reference is now made to Figs. 10A and 10B. Heart valve treatment device 10 has been retracted (“un-landed”), for example, by a 20 mm movement in the retraction direction, so the device can either be removed or repositioned for transition between cusps.
[0039] Reference is now made to Figs. 11A and 11B, which illustrate partial contraction of scoring element 32 for movement (rotation and/or translation) inside of the centering stabilizer 36.