Device for treating valvular insufficiency

Abstract

To provide a device for treating valvular regurgitation.SOLUTION: A device for treating valvular regurgitation comprises an expandable anchor including a plurality of struts configured to transition from a first configuration when confined within a tube to a second configuration when released from the tube, and a spacer attached to the expandable anchor and configured to provide a coaptation surface to at least one valve leaflet. The transition of the plurality of struts includes an expansion phase in which ends of the struts curl outward and an inversion phase in which ends of the struts curl inward. The spacer includes a column enclosed by an inflatable balloon.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] [Related Applications] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 089,587, filed October 9, 2020, the contents of which are incorporated herein by reference in their entirety.

[0002] FIELD AND BACKGROUND OF THE INVENTION The present invention relates to a device for treating valvular insufficiency and a catheter system for delivering the device to the heart. Embodiments of the invention relate to a device including a transvalvular spacer attached to an atraumatic anchor positionable within the atrium.

[0003] Valvular insufficiency is a heart condition in which the heart valves do not close completely, causing regurgitation or leakage of the valves.

[0004] Anatomically, valves are part of the heart's dense connective tissue, known as the cardiac skeleton, and are responsible for regulating blood flow through the heart and great vessels. Valve incompetence due to impairment or malfunction can impair cardiac function and reduce blood flow throughout the body. Treatments for damaged valves include medical therapy alone or surgical valve repair (valvuloplasty) or replacement (insertion of a prosthetic heart valve).

[0005] Atrioventricular valve incompetence can cause blood to leak or flow from the ventricles into the atria (regurgitation) rather than being pushed out of the ventricles during contraction.

[0006] Mitral regurgitation (mitral valve insufficiency) is a common valvular insufficiency that is typically treated by mitral valve replacement or repair via open-heart surgery or minimally invasive (percutaneous) medical procedures. Percutaneous procedures for mitral valve repair include percutaneous mitral valve replacement, augmented mitral valve coaptation, end-to-end percutaneous mitral valve repair (plication), percutaneous chordae tendineae repair, percutaneous mitral annuloplasty, and left ventricular remodeling.

[0007] Percutaneous mitral valve replacement / repair is less traumatic to the patient and can be used in patient populations who are not candidates for open-heart surgery (due to age or comorbidities), but challenges remain in terms of implant delivery, positioning, and long-term stability and functionality within the heart.

[0008] Therefore, it would be highly advantageous to have a device for correcting valvular insufficiency and a system for providing the same that overcomes the limitations of currently used approaches. Summary of the Invention

[0009] According to one aspect of the present invention, there is provided a device for treating valvular regurgitation, the device comprising: an expandable anchor including a plurality of struts designed to transition from a straight configuration when confined within a delivery tube to a crown-shaped configuration when released from the tube, the transition including a radial expansion phase in which the ends of the struts curl away from a centerline of the crown-shaped configuration and an inversion phase in which the ends of the struts curl toward the centerline of the crown-shaped configuration; and a transvalvular spacer attached to the expandable anchor and configured to provide a coaptation surface for the valve leaflets.

[0010] According to an embodiment of the present invention, the transvalvular spacer includes a flexible column encased in an inflatable balloon.

[0011] According to an embodiment of the present invention, the flexible column is laminated with a polymer sheath.

[0012] According to an embodiment of the present invention, the balloon is bonded to the polymer sheath.

[0013] According to an embodiment of the present invention, the flexible column is a tube with a cutout.

[0014] According to an embodiment of the present invention, the plurality of struts are attached around a proximal end portion of the flexible column.

[0015] According to an embodiment of the present invention, the polymer sheath includes an opening covered by a tube valve.

[0016] According to an embodiment of the present invention, the balloon is fluid-fillable through the tube valve.

[0017] According to an embodiment of the present invention, the balloon is fillable with the fluid when the flexible column is mounted over a guidewire.

[0018] According to an embodiment of the invention, the distal end of the flexible column includes a seal for sealing around the guidewire.

[0019] According to an embodiment of the present invention, the flexible column includes tabs for guiding an actuation mechanism to the tube valve.

[0020] According to an embodiment of the invention, the expandable anchor includes seven struts.

[0021] According to an embodiment of the invention, when the expandable anchor is expanded, each of the seven struts diverges and reconverges along the length of each strut.

[0022] According to an embodiment of the present invention, adjacent struts of the seven struts are interconnected in the region between the bifurcation and the rejunction.

[0023] According to an embodiment of the present invention, the ends of the struts are spoon-shaped.

[0024] According to an embodiment of the present invention, the ends of the struts include eyelets.

[0025] According to an embodiment of the invention, the portion of the flexible column interposed between the expandable anchor and the transvalvular spacer includes a helical cutout.

[0026] According to an embodiment of the invention, the transvalvular spacer is removably attached to the expandable anchor.

[0027] According to an embodiment of the present invention, at least one end of the inflatable balloon is inverted inward.

[0028] According to an embodiment of the present invention, the inflatable balloon contains a solution having an osmotic potential greater than that of blood.

[0029] According to an embodiment of the invention, the expandable anchor includes a graspable element at its proximal end.

[0030] According to an embodiment of the present invention, said graspable element is a ball-shaped element.

[0031] According to another aspect of the present invention, there is provided a method for treating valvular regurgitation, comprising: (a) delivering to the heart a device comprising: (i) an expandable anchor including a plurality of struts designed to transition from a straight configuration when confined within a delivery tube to a crown-shaped configuration when released from the tube, the transition including a radial expansion phase in which the ends of the struts curl away from the center of the crown-shaped configuration and an inversion phase in which the ends of the struts curl toward the center of the crown-shaped configuration; and (ii) a transvalvular spacer attached to the expandable anchor and including a flexible column encased in an inflatable balloon designed to provide a coaptation surface for the valve leaflets; and (b) releasing the expandable anchor within the atrium such that the transvalvular spacer is positioned within the valve; and (c) at least partially inflating the inflatable balloon.

[0032] According to an embodiment of the present invention, (c) is provided using a solution having an osmotic potential greater than that of blood.

[0033] According to an embodiment of the present invention, step (c) is performed before step (b).

[0034] According to another aspect of the present invention, there is provided a catheter system for delivering a device for treating valvular regurgitation, the system comprising a coaxial catheter assembly including: (a) a first catheter including a distal grasper for grasping the device; (b) a second catheter movable along the first catheter and having a distal locking cup for locking the grasper therein; and (c) a third catheter movable along the second catheter.

[0035] According to an embodiment of the invention, the grasper includes an O-ring for sealing against the device.

[0036] According to an embodiment of the invention, the catheter assembly includes at least one fluid conduit for supplying fluid to the device when attached.

[0037] According to an embodiment of the present invention, the coaxial catheter assembly further comprises a movable elongate element extending from a distal end thereof, the elongate element for opening a valve of the device to allow fluid delivery thereto from the at least one fluid conduit.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. In case of conflict, the present specification, including definitions, will control. Furthermore, the materials, methods, and examples are illustrative only and not intended to be limiting.

[0039] The present invention will now be described, by way of example only, with reference to the accompanying drawings. With particular reference to the details of the drawings herein, it is emphasized that the specific details shown are presented solely for illustrative purposes to aid in the understanding of preferred embodiments of the invention, and for the purpose of providing what is believed to be the most useful and readily understandable explanation of the principles and conceptual aspects of the invention. In this regard, no attempt has been made to show the structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, and the description, taken in conjunction with the drawings, will make apparent to those skilled in the art how several forms of the invention may be embodied in practice. [Brief explanation of the drawings]

[0040] [Figure 1] 10A-10C illustrate one embodiment of the anchor portion of the device. [Figure 2] 1A-1C illustrate one embodiment of the device including an anchor portion and an attached spacer portion. [Figure 3] 10(A)-(D) show the expansion of the anchor portion when pushed out from the restraining catheter tube. [Figure 4] FIG. 1 illustrates one embodiment of the device showing the internal components of the spacer portion. [Figure 5] FIG. 10 shows the balloon of the spacer portion, showing the distal end of the balloon everted. [Figure 6] FIG. 10 shows the bent tab on the central column of the spacer portion that controls access to the balloon fill valve. [Figure 7A] FIG. 1 illustrates one embodiment of a catheter system for delivering the device to the heart. [Figure 7B] FIG. 1 illustrates one embodiment of a catheter system for delivering the device to the heart. [Figure 8] FIG. 7C shows the distal end of the catheter system of FIGS. 7A-7B detached from the proximal end of the device of the present invention. [Figure 9]FIG. 7C shows the distal end of the catheter system of FIGS. 7A-7B engaged with the proximal end of a device of the present invention. [Figure 10] (A) shows the device positioned in the heart during the systolic phase of the heart, and (B) shows the device positioned in the heart during the diastolic phase of the heart. DETAILED DESCRIPTION OF THE INVENTION

[0041] The present invention relates to a device that can be used to correct valvular insufficiency. Specifically, the present invention can be used to percutaneously treat valvular insufficiency by delivering, positioning, and securing a device that includes a transvalvular spacer attached to an atraumatic atrial anchor.

[0042] The principles and operation of the present invention may be better understood with reference to the drawings and accompanying descriptions.

[0043] Before describing at least one embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application to what is set forth in the following description or illustrated by the examples. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

[0044] Implants and approaches for correcting valvular regurgitation due to incomplete valve coaptation have been described in the prior art. Such devices include an atrial or ventricular anchor attached to a spacer that is placed within the valve opening to seal against the native valve leaflets when closed. While such implants are generally effective in sealing against the closed valve leaflets, they are often delivered or secured in a manner that is traumatic to the cardiac tissue.

[0045] The inventors have devised an implant and delivery system that puts the present invention into practice while addressing these limitations of prior art devices, while offering numerous additional advantages in function and long-term stability.

[0046] The present invention is characterized by the following. (i) an expandable atrial anchor that exerts a radially outward force to secure the inner wall of the atrium, is atraumatic to the atrial tissue, and is stable over multiple cardiac cycles; (ii) an expansion mechanism that maintains the potentially traumatic end of the expandable atrial anchor away from the inner atrial wall; (iii) Valve coaptation spacers that can be individually sized (diameter) to meet the patient's needs before or after delivery and at any time during the procedure. (iv) A valve spacer that can self-size (diameter) according to the patient's needs after delivery. (v) a delivery system that firmly grips the graft throughout the expansion of the expandable atrial anchor, allowing the expandable atrial anchor to self-position in an optimal orientation within the atrium; (vi) Atraumatic expandable anchors with anatomical self-positioning (vii) Expandable anchors that allow for assessment of anatomical in situ efficacy while maintaining full retrievability. (viii) A delivery system capable of positioning, filling, draining, and retrieving the implant.

[0047] Thus, according to one aspect of the present invention, there is provided a device (implant) for treating valvular insufficiency. As used herein, the term "valvular insufficiency" refers to any valve leaflet dysfunction that leads to valve leakage and regurgitation. Valvular insufficiency can be caused by, for example, congenital heart disease, infection, valvular stenosis, annular dilation or stretching, chordae laceration, dilated cardiomyopathy, or valve prolapse.

[0048] The device of the present invention includes an expandable anchor designed to transition from a straight configuration (collapsed state) to a crown-shaped configuration (expanded state). This transition includes a radial expansion phase in which the ends of the anchor curl away from the centerline (of the device) and an inversion phase in which the ends of the anchor curl toward the centerline. This transition between the collapsed and expanded states of the anchor ensures that, when expanded within the atrium, the (free) ends of the anchor do not contact the inner wall of the atrium during any phase of expansion.

[0049] The device of the present invention further includes a transvalvular spacer attached to the distal end (opposite the delivery side) of the anchor. The spacer can be a solid spacer, a foam spacer, or any other spacer capable of providing a coaptation surface for the valve leaflets (e.g., sealing against the leaflets during closure). Spacer embodiments including a flexible column encased in an inflatable balloon are described further below.

[0050] To allow for controlled delivery of the device and maintain control over the anchor when expanded within the atrium, the device further includes a ball-shaped graspable element at the proximal end, which is graspable via a grasper and locking sleeve mechanism located at the distal end of the delivery catheter.

[0051] The ball-shaped graspable element has multiple functions. (i) The device can be mounted regardless of orientation (ii) When coupled with the locking cup and O-ring, the ball forms a fluid-tight seal between the delivery system and the implant up to 2 bar (0.2 MPa). (iii) This fluid-tight seal is maintained regardless of the rotational position of the implant and lateral tilt angles up to 7.5 degrees.

[0052] These features allow the anchor to rotate freely while remaining axially attached to the delivery system and maintaining a fluid-tight seal. This is especially important during delivery, as the implant must navigate bends in the DS, resulting in rotation of the implant. It also allows the anchor to rotate within the anatomy and move to the most energy-efficient position during deployment.

[0053] Delivery of the device of the present invention is accomplished using a dedicated catheter system (delivery system) that has several unique features.

[0054] The catheter system includes three coaxial catheters, each independently longitudinally movable. The distal ends of the intermediate and outer catheters (also referred to herein as the second and third catheters, respectively) include a grasper (intermediate catheter) and locking sleeve (outer catheter) mechanism for grasping and releasing the anchor (and device). The distal end of the intermediate catheter also includes a seal for sealing against a fluid port located on the graspable element of the device. Such a seal allows the balloon component of the spacer to be filled and emptied via a dedicated balloon valve actuated from the catheter system.

[0055] Referring now to the drawings, FIGS. 1-6 illustrate one embodiment of the present device, referred to herein as device 10. FIG.

[0056] FIG. 1 illustrates the anchor 12 portion of device 10 in an expanded state. Anchor 12 includes struts 14 connected to a central column 16. In the embodiment shown in FIG. 1, adjacent struts 14′ and 14″ of each strut pair (seven pairs shown) follow parallel paths away from central column 16, diverging at 18 and reuniting at 20. Each strut pair terminates in a spoon-shaped portion 22 containing a pinhole 24, which may be used as a connection point for controlled strut deployment. The spoon-shaped portion 22 of the crown tip is specially configured to prevent the leading edge of the crown tip from contacting the catheter lumen when the graft is covered. The increased surface area of ​​the crown tip (compared to the crown arms themselves) will reduce the likelihood of the tip causing any tissue damage during or after deployment.

[0057] The struts 14 are fabricated from nitinol or stainless steel, for example, by laser cutting a tube or sheet. The struts 14 have a width of 0.2-0.6 mm and a thickness of 0.2-0.5 mm. The anchor 12 has an expanded outer diameter (OD) of 50-80 mm (e.g., 70.9 mm) and a height of 15-30 mm (e.g., 20.7 mm), and a collapsed OD of 2-4 mm (e.g., 3.2 mm) and a length of 70-100 mm (e.g., 93.9 mm).

[0058] 2 shows the anchor 12 and attached balloon 40. The balloon 40 and column 16 are collectively referred to herein as a spacer 35.

[0059] The struts 14 are pre-formed so that the ends of the struts 14 (e.g., spoon-shaped portions 22) do not contact the inner surface of the atrium when transitioning from a collapsed configuration (straightened within the delivery catheter) to a fully expanded configuration.

[0060] Figures 3(A)-3(D) show the movement of the struts and their ends during expansion; the spacer 35 and balloon 40 are also shown in these figures. When the anchor 12 initially emerges from the delivery catheter, the ends 15 of the struts 14 move radially outward (away from the longitudinal centerline of the device 10). At this point, the diameter of the partially expanded anchor 12 is 10-20 mm, which is much smaller than the diameter of the atrial space in patients with moderate to severe valvular regurgitation. Figure 3(B) shows the maximum diameter (30-40 mm) with the ends 15 facing outward, and the anchor diameter remains smaller than the diameter of the atrium. Further expansion (Figures 3(C)-3(D)) causes the ends 15 to curl radially inward (toward the centerline of the device 10), expanding the anchor to a final diameter of 60-80 mm without risking the ends 15 contacting the inner wall of the atrium. During the expansion stage shown in Figures 3(C)-3(D), end 15 follows a curved path that corresponds to the radius of curvature of the struts exiting the catheter tip.

[0061] The central column 16 spans the length of the device 10 and is configured with lateral flexibility (at its proximal portion 17) to provide tiltable (angled side to side, e.g., pendulum-like) flexibility to the attached balloon 40 (Figure 2). This allows the spacer 35 (central column 16 and balloon 40) to accommodate asymmetric valve closure and off-center placement of the anchor 12. The central column 16 can be a polymer or nitinol tube with sidewall cutouts 27 (helical, double-helical, or bowtie-shaped) at the proximal portion 17. The central column 16 is subject to cyclic axial loads throughout its life cycle due to cyclic pressure differentials between the ventricle and atrium. The cutouts allow flexibility of the central column during delivery, while maintaining sufficient axial stiffness to prevent buckling under axial loads. Figure 4 shows the helical sidewall cutout pattern at the proximal portion 17 of the central column 16. The central column 16 may be 50-70 mm long (e.g., 69.5 mm) and have diameters of 2-4 mm OD x 1-3 mm ID (WT=0.44 mm). The lumen 23 (FIGS. 4 and 6) running the length of the central column 16 may be 1-2 mm in diameter.

[0062] The central column 16 or its distal portion 19 (the portion surrounded by the balloon 40, FIGS. 2 and 4) is covered with a polymer (e.g., Carbothane 55D) sheath 21 (FIGS. 4 and 6) to which the balloon 40 is bonded. The distal portion 32 of the central column 16 can include a plug 34 to seal around a guidewire.

[0063] The tube 31 includes an inwardly angled tab 37 to facilitate access to the valve 39 of the balloon 40 (FIGS. 4 and 6). The valve 39 can be a silicone tube covered over the portion of the central column 16 that includes the opening to the volume of the balloon 40. The valve 39 can be opened (pushed out of the opening in the central column 16) by directing a valve actuation mechanism 33 (e.g., a dedicated elongated element 41, FIG. 6) through the lumen 23 (e.g., from a delivery catheter) and under the tab 37 (FIG. 6). Once the valve 39 is opened, the balloon 40 can be filled through the lumen 23 with its distal end blocked by the plug 34. The plug 34 seals through the lumen 23 with or without a guidewire passing therethrough.

[0064] The proximal end 26 of the central column 16 includes a graspable element 28 for securing the device 10 to a catheter system (described further below).

[0065] The graspable element 28 (best seen in FIG. 4) is designed to be graspable within an actuatable grasper that includes at least two hemispherical halves configured to receive (cup) the element 28. The element 28 is generally ball-shaped with a flattened proximal end 30.

[0066] The graspable element 28 includes an opening at the proximal end 30, which therefore also serves as a fluid port for filling the balloon 40 of the spacer 35 when the device 10 is secured to a catheter system.

[0067] The balloon 40 can be bonded to the sheath 21 with its end facing outward (as shown in FIGS. 2 and 4), or the balloon 40 can be bonded to the sheath 21 with its distal end 44 everted inward (FIG. 5). This configuration prevents potentially traumatic ends of the implant from facing the tissue.

[0068] Balloon 40 is fabricated from a semi-compliant polymer using techniques well known in the art. Balloon 40 can have a parallel length of 42.0±1.5 mm and a diameter of 15 mm (when fully inflated). The pressure range of balloon 40 can be from 0 atmospheres (atm) to 0.25 atmospheres during normal operation.

[0069] The wall of the balloon 40 can be impermeable or semi-permeable (e.g., permeable to fluids such as water but not to cells). A permeable balloon wall can be used for osmotic filling, as described below.

[0070] Balloon 40 can be filled with fluid (e.g., saline or osmotic solution) through a fluid port in graspable element 28. Filling through a port in graspable element 28 (through a tube valve at 39) is described above and further below with respect to the catheter system used for delivery of device 10.

[0071] The balloon 40 can be filled to its final volume and pressure following delivery of the device 10 (i.e., following expansion of the anchor 12). The atraumatic nature of the anchor system allows the device to be fully deployed and the effectiveness of treatment to be immediately assessed. If the device does not satisfactorily reduce reflux, the balloon can be deflated and the entire device can be retrieved into the sheath and removed from the patient.

[0072] The effectiveness of the balloon 40 in leaflet coaptation can be tested prior to implanting the device. This can be accomplished by simply using a similarly sized "off-the-shelf" balloon and advancing it into place along a guidewire across the valve. This allows the clinician to assess the effectiveness of spacer therapy before using the device, potentially reducing the risk of treating patients who do not respond optimally to spacer-based valve repair.

[0073] As described above, balloon 40 can be semi-permeable to allow for osmotic filling. Balloon 40 can be partially inflated with an osmotic solution (e.g., a saline control solution) having an osmotic potential greater than that of blood (e.g., an osmolality of 300-500 mOsm / L).

[0074] The osmotic potential of blood is fixed. Therefore, the osmotic potential of the solution used to fill the balloon 40 will precisely determine the final pressure within the balloon. The osmotic mechanism ensures that the pressure in the balloon remains constant. Also, the pressure to which the balloon is filled during surgery does not need to be precise, as the osmotic mechanism will resolve any differences and reach equilibrium.

[0075] For months to years before intervention, the patient's cardiovascular system compensates for the impaired valve function. Once intervention is performed, valve function is restored, but the cardiovascular system is not accustomed to this change. Consequently, patients undergoing valve repair and / or replacement often experience symptoms related to pressure overload. A potential treatment for this is the use of a balloon to inflate during surgery. In this manner, the balloon may only partially improve valve function acutely. This would allow the cardiovascular system to remodel over the following weeks to months as the osmotic effect of the balloon gradually increases the internal pressure / diameter, which may further improve valve function.

[0076] As described above, the device 10 of the present invention is configured to correct imperfect leaflet coaptation of a heart valve. The device 10 can be used to correct atrioventricular valve coaptation (either bicuspid or tricuspid) by delivering the device 10 using a catheter system. An example would be to repair the tricuspid valve. For this procedure, the device would be delivered via a transcatheter approach, either via the jugular vein through the superior vena cava, or alternatively, via the femoral vein through the inferior vena cava. For the mitral valve, a transseptal approach would be preferred to access the left atrium and mitral valve.

[0077] 7A-9 illustrate one embodiment of a catheter system, referred to herein as system 100.

[0078] The catheter system includes three coaxial catheters: an outer catheter 102, a middle catheter 104, and an inner catheter 106.

[0079] The catheter 106 includes a stretch compensation mechanism to compensate for the elastic properties of the polymer tubing of the delivery system and the length of the polymer tubing. Because elasticity is determined by percentage, this elastic property can result in a large change in absolute length at the distal end of the catheter 106. The resulting change in length can cause relative movement between components at the distal end that can be compensated for by spring loading portions of the system.

[0080] The compensation mechanism includes two components, a locking cup 110 and a retainer 112, which work together to grip the graspable element 28 of the device 10. Because the catheter 106 may be subjected to large tensile loads during implant deployment and retrieval, a compression spring (in the handle) is used to enable the locking cup 110 to maintain its position relative to the retainer 112. In this manner, the locking cup 110 and retainer 112 remain locked in a closed position at the distal end of the catheter 106, and the graspable element 28 of the device 10 remains securely attached within the locking cup 110. An O-ring 114 disposed within the retainer 112 maintains a seal against the front face 116 of the graspable element 28.

[0081] The catheter system 100 is used to deliver the device 10 as follows. Prior to delivery, the system 100 is prepared in a benchtop sterile area by arranging the components and accessories of the system 100 and testing each one and the system as a whole. The device 10 is removed from its packaging, loaded into the catheter system via the graspable element 28, and drawn into the steerable inner catheter 104. The steerable inner catheter 104 with the covered graft 10 can then be loaded into the outer catheter 102.

[0082] In an exemplary transseptal approach, jugular venous access is created and an 18F introducer is placed through the jugular venous access. Femoral venous access is created and a 6F introducer is placed through it. A transesophageal echocardiogram (TEE) or transthoracic echocardiogram (TTE) probe is placed using standard procedures to assess tricuspid valve function. Under fluoroscopic guidance, a compatible 1.5 ml balloon catheter is inserted through the 18F introducer and advanced through the tricuspid valve, the right ventricle, into the pulmonary artery, and into the right atrium. A 0.035" (0.035 inch) guidewire is inserted through the balloon catheter into the pulmonary artery, and the balloon catheter is withdrawn while the wire is held steady. Contrast agent is injected through a 6F introducer to identify the ventricular contours and the height of the tricuspid valve. Under fluoroscopic guidance, a commercially available 15 mm diameter balloon catheter is passed over the wire so that the balloon is positioned above the tricuspid valve. The balloon is inflated, and intravalvular regurgitant flow is assessed by echocardiography. If sufficient regurgitant flow is confirmed, the balloon is withdrawn and the procedure is continued; otherwise, the balloon is withdrawn and the procedure is discontinued.

[0083] The proximal end of the guidewire is inserted through the device 10 and catheter system 100. While the guidewire remains stationary relative to the anatomy, the system 100 is advanced to approximately mid-atrial height. Steerable catheters 102 and 104 can be used to properly orient the system relative to the patient's anatomy. Once adequately positioned, the tip of the anchor 12 is deployed in a controlled manner into the right atrium under fluoroscopic guidance while continuously assessing valve function with echocardiography. Once the anchor 12 is deployed, leaflet motion and device 10 position are assessed under echocardiography and / or fluoroscopy with contrast injection through a 6F catheter. If the tricuspid valve exhibits typical motion, the procedure continues; if not, the tip of the anchor 12 is retracted, repositioned, and the deployment repeated.

[0084] A 20-50 ml syringe filled with (10-50%) 20% saline / sterile water contrast agent vehicle solution is attached to the inflation valve / port of the balloon 40, and the guidewire is retracted long enough to keep the distal plug sealed. The balloon 40 is then inflated under fluoroscopic guidance. As the balloon 40 approaches its full capacity, periodic indentations by the closing leaflets should be clearly visible. The balloon is further inflated until the leaflets no longer indent the balloon and the balloon reaches its nominal diameter. The catheters 102 and 104 are then retracted so that the catheter 106 is fully extended, allowing for maximum in situ graft movement. An echocardiogram is then used to verify the position of the balloon 40 and its effectiveness in reducing regurgitation.

[0085] If the balloon 40 is not effective in reducing reflux, the device 10 is withdrawn and the system 100 and attached device 10 are removed. If the position of the device 10 is not satisfactory, the balloon 40 can be deflated via vacuum and the device 10 can be repositioned.

[0086] If the position and function of the device 10 is satisfactory, the valve actuation mechanism is unlocked and retracted to seal the spacer balloon while the diameter and shape of the balloon 40 is monitored fluoroscopically. The device 10 can then be released from the catheter system 100, after which the guidewire and catheter system 100 are removed.

[0087] When the anchor 12 is positioned in the atrium and the balloon 40 is inflated, the spacer 35 of the device 10 seals against the partially closed valve leaflets during systole (FIG. 10(A)) and allows blood flow through the valve during diastole (FIG. 10(B)) when the leaflets are fully open.

[0088] As used herein, the term "about" refers to ±10%.

[0089] Additional objects, advantages, and novel features of the present invention will become apparent to those skilled in the art upon examination of the following examples thereof, which are not intended to be limiting. [Example]

[0090] Reference is now made to the following examples, which together with the above descriptions illustrate the invention in a non-limiting manner.

[0091] Animal experiments To evaluate the clinical safety and performance of the device and delivery system, a chronic animal study was conducted using a healthy pig model. The device was implanted in six animals with a 90-day follow-up period.

[0092] The purpose of this animal study was to evaluate the safety and size of the device.

[0093] Implant delivery and placement was performed in each animal using the steps described above. Histopathological and long-term clinical results were used to demonstrate the safety of the system.

[0094] Six animals were monitored with angiographic imaging at 1 week, 1 month, 2 months, and 3 months after treatment. After the final monitoring, the animals were sacrificed. A thorough evaluation of the treated animals revealed no clinically significant device-related effects. The grafts were intact and well positioned.

[0095] [Histological analysis results] After animal sacrifice, the hearts were removed and sent for histological analysis to assess safety parameters such as structural damage, tissue in-growth, and thrombosis.

[0096] Analysis revealed no structural damage to the cardiac tissue. The valve leaflets were intact, along with the ventricular wall. There was no interference with the papillary muscles or chordae. Smooth muscle tissue growth was observed in the coronal arms, and no thrombus formation was observed.

[0097] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

[0098] While the present invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims. All publications, patents, and patent applications mentioned in this specification are incorporated herein 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 herein by reference. Furthermore, citation or identification of any document in this application shall not be construed as an admission that such document is available as prior art to the present invention.

[0099] Additionally, the priority document of this application is incorporated herein by reference in its entirety.

Claims

1. 1. A device for treating valvular regurgitation comprising: an expandable anchor including a plurality of struts configured to transition from a first configuration when confined within a tube to a second configuration when released from the tube, the transition including an expansion stage in which ends of the plurality of struts curl outward and an inversion stage in which ends of the plurality of struts curl inward; a spacer configured to provide a coaptation surface for at least one leaflet and attached to the expandable anchor, the spacer including a column encased in an inflatable balloon. Device.

2. the expanding step is a step in which ends of the struts curl outward from a centerline of the second configuration.

10. The apparatus of claim 1.

3. the inverting step is a step in which the ends of the struts curl toward a centerline in a crown-like configuration.

3. The apparatus of claim 2.

4. the first configuration is a straight configuration and the second configuration is a crown configuration; 10. The apparatus of claim 1.

5. the column includes a tab configured to facilitate access to the valve, the tab being angled inwardly relative to the column; 10. The apparatus of claim 1.

6. the column is covered with a polymer sheath, the polymer sheath being bonded to the inflatable balloon at a portion of the column; 10. The apparatus of claim 1.

7. the inflatable balloon is bonded to the polymer sheath, and the inflatable balloon includes at least one end facing outward or inverted; 7. The apparatus of claim 6.

8. the inflatable balloon includes an inverted end, the inverted end being bonded to the polymer sheath; 7. The apparatus of claim 6.

9. the column includes a lumen extending along the length of the column, the lumen configured to accommodate a valve actuation mechanism or a guidewire; 10. The apparatus of claim 1.

10. the column includes at least one cutout formed along a proximal portion of the column, the at least one cutout configured to provide lateral flexibility; 10. The apparatus of claim 1.

11. the column includes a distal portion including a plug configured to seal around a guidewire; 10. The apparatus of claim 1.

12. the expandable anchor includes seven struts, each strut branching and rejoining along its length; 10. The apparatus of claim 1.

13. the expandable anchor includes a strut including a spoon-shaped portion at an end thereof, the spoon-shaped portion including a pinhole; 10. The apparatus of claim 1.

14. The expandable anchor includes struts including eyelets at their ends, the eyelets configured for use as connection points.

10. The apparatus of claim 1.

Images