Leaflet extension device for heart valve leaflets

Abstract

To provide a leaflet extension device for heart valve leaflets, and method for treating the heart valve leaflets.SOLUTION: A leaflet extension device for resolving regurgitation in heart valves, the device comprises an expandable member and a cover. The expandable member has a stabilizing portion, a fixation member in opposition to the stabilizing portion, and a coaptation portion between the stabilizing portion and the expandable member. The stabilizing portion and the fixation member clamp a first native leaflet between the stabilizing portion and the fixation member. The coaptation portion projects from the stabilizing portion and the fixation member inwardly with respect to the first native leaflet of a heart valve such that the coaptation portion functionally extends the first native leaflet. The cover is attached to at least the coaptation portion of the expandable member.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates generally to implants for repairing regurgitant or incompetent heart valves and methods of implanting such implants. The present invention is particularly useful for repairing regurgitant mitral valves. [Background technology]

[0002] Conditions that adversely affect the proper functioning of the mitral valve include, for example, mitral regurgitation, mitral valve prolapse, and mitral valve stenosis. Mitral regurgitation is a heart condition in which the leaflets of the mitral valve fail to coapt and stick together at peak systolic pressure, resulting in abnormal leakage of blood from the left ventricle to the left atrium. Several structural factors can adversely affect the proper closure of the mitral valve leaflets. For example, many patients with heart disease experience dilation of the myocardium, resulting in an enlarged mitral valve annulus. The enlarged mitral valve annulus makes it difficult for the leaflets to coapt during cardiac contraction. Stretching or avulsion of the chordae tendineae, the tendons connecting the papillary muscles to the underside of the mitral valve leaflets, can also adversely affect the proper closure of the mitral valve annulus. For example, rupture of the chordae tendineae can cause the leaflets to prolapse into the left atrium due to inappropriate tension on the leaflets. Abnormal regurgitation can also occur when papillary muscle function is impaired, for example, due to ischemia: when the left ventricle contracts during systole, the affected papillary muscles do not contract sufficiently to close properly.

[0003] Mitral valve prolapse, or abnormal upward bulging of the mitral valve leaflets into the left atrium, can cause irregular mitral valve behavior and result in mitral valve regurgitation. Normal mitral valve function can also be adversely affected by mitral valve stenosis, or narrowing of the mitral orifice, which creates left ventricular filling impedance during diastole.

[0004] Mitral regurgitation is often treated with diuretics and / or vasodilators to reduce the amount of blood leaking back into the left atrium. Other treatments, such as surgical procedures (open and endovascular), have also been used to either repair or replace the mitral valve. For example, typical repair procedures involve cinching or ablation of portions of the dilated annulus.

[0005] Cinching of the annulus has typically been achieved by implantation of an annular or circumferential annular ring that is anchored to the annulus or surrounding tissue. Other repair techniques have also involved suturing or clipping the leaflets into their partial attachments to one another.

[0006] Alternatively, more invasive procedures have involved total heart valve replacement, in which a mechanical valve or biological tissue is implanted in the heart in place of the mitral valve. These invasive procedures have traditionally been performed through a large open thoracotomy and are thus extremely painful, involve significant morbidity, and require a long recovery period.

[0007] However, many repair and replacement procedures can present additional problems for the patient as a result of device durability or improper sizing of the annuloplasty ring or replacement valve. Furthermore, many repair procedures are highly dependent on the skill of the cardiac surgeon, where poorly or incorrectly placed sutures can adversely affect the success of the procedure.

[0008] Compared to other heart valves, some portions of the mitral valve annulus have limited significant radial support from surrounding tissue, and the mitral valve has an irregular and unpredictable shape. For example, the inner wall of the mitral valve is bounded only by a thin vascular wall that separates the mitral valve annulus from the lower portion of the aortic outflow tract. As a result, the substantial radial forces exerted on the mitral valve annulus can cause collapse of the lower portion of the aortic outflow tract, with potentially fatal consequences.

[0009] The chordae tendineae of the left ventricle are a frequent obstacle during deployment of mitral valve repair devices. The labyrinthine web of chordae tendineae within the left ventricle makes it extremely difficult to navigate and position a deployment catheter for mitral valve repair. Summary of the Invention [Problem to be solved by the invention]

[0010] Given the problems associated with current procedures, there is a continuing need for simple, effective, and minimally invasive devices and methods for treating dysfunctional heart valves. [Means for solving the problem]

[0011] The present invention relates to heart valve devices, particularly devices for treating regurgitant or dysfunctional heart valves. While many of the applications are described with respect to the mitral valve, the invention is not limited to mitral valve applications. The devices of the present invention are intended to repair, but not replace, the entire natural valve.

[0012] Some embodiments of the present invention functionally lengthen one or more native leaflets to facilitate coaptation with the other leaflets, thereby alleviating insufficiency without penetrating the native leaflets. Some embodiments of the present invention are described with respect to the posterior leaflet of the mitral valve, and these embodiments provide an atraumatic coaptation surface for the anterior leaflet. However, the present invention can also be used to provide an atraumatic coaptation surface for the posterior leaflet while functionally lengthening the anterior leaflet. [Brief explanation of the drawings]

[0013] [Figure 1] A schematic diagram of the natural mitral valve. [Figure 2A] 1A-1C illustrate leaflet extension devices configured for attachment to a native heart valve in accordance with the present invention. [Figure 2B] 1A-1C illustrate leaflet extension devices configured for attachment to a native heart valve in accordance with the present invention. [Figure 2C]1A-1C illustrate leaflet extension devices configured for attachment to a native heart valve in accordance with the present invention. [Figure 3] FIG. 1 is a side view of a frame-type expandable member according to the present invention. [Figure 4] 1 illustrates a leaflet extension device implanted within the mitral valve in accordance with the present invention. [Figure 5A] 10A-10C illustrate a method of implanting a leaflet extension device in accordance with the present invention. [Figure 5B] 10A-10C illustrate a method of implanting a leaflet extension device in accordance with the present invention. [Figure 5C] 10A-10C illustrate a method of implanting a leaflet extension device in accordance with the present invention. [Figure 5D] 10A-10C illustrate a method of implanting a leaflet extension device in accordance with the present invention. [Figure 5E] 10A-10C illustrate a method of implanting a leaflet extension device in accordance with the present invention. [Figure 6A] 1A-1C show a leaflet extension device according to the present invention. [Figure 6B] 1A-1C show a leaflet extension device according to the present invention. [Figure 7A] 10A-10C show the stabilizing portion of the leaflet extension device according to the present invention. [Figure 7B] 10A-10C show the stabilizing portion of the leaflet extension device according to the present invention. [Figure 8A] 1A-1C show leaflet extension devices according to the present invention. [Figure 8B] 1A-1C show leaflet extension devices according to the present invention. [Figure 9A] 10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 9B] 10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 9C] 10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 9D] 10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 9E]10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 10A] 10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 10B] 10A-10C show a leaflet distraction device with fixation members extending between the chordae in accordance with the present invention. [Figure 11A] 1A-1C show leaflet extension devices according to the present invention. [Figure 11B] 1A-1C show leaflet extension devices according to the present invention. [Figure 12] 1A-1C show leaflet extension devices according to the present invention. [Figure 13A] 1A-1C show leaflet extension devices according to the present invention. [Figure 13B] 1A-1C show leaflet extension devices according to the present invention. [Figure 14A] 1A-1C show leaflet extension devices according to the present invention. [Figure 14B] 1A-1C show leaflet extension devices according to the present invention. [Figure 14C] 1A-1C show leaflet extension devices according to the present invention. [Figure 14D] 1A-1C show leaflet extension devices according to the present invention. [Figure 14E] 1A-1C show leaflet extension devices according to the present invention. [Figure 14F] 1A-1C show leaflet extension devices according to the present invention. [Figure 14G] 1A-1C show leaflet extension devices according to the present invention. [Figure 15A] 1A-1C show leaflet extension devices according to the present invention. [Figure 15B] 1A-1C show leaflet extension devices according to the present invention. [Figure 16] 10A-10C show the stabilizing portion of the leaflet extension device according to the present invention. [Figure 17A] 10A-10C show additional leaflet extension devices according to the present invention. [Figure 17B] 10A-10C show additional leaflet extension devices according to the present invention. [Figure 17C] 10A-10C show additional leaflet extension devices according to the present invention. [Figure 17D] 10A-10C show additional leaflet extension devices according to the present invention. [Figure 18A] 13A-13C illustrate a leaflet extension device with an inflatable expandable member. [Figure 18B] 13A-13C illustrate a leaflet extension device with an inflatable expandable member. [Figure 18C] 13A-13C illustrate a leaflet extension device with an inflatable expandable member. [Figure 19] 10A-10C show an expandable member for a leaflet extension device according to the present invention. [Figure 20] 10A-10C show an expandable member for a leaflet extension device according to the present invention. [Figure 21] 1 is a close-up view of an expandable member with a friction element according to the present invention. [Figure 22] 1A-1C show a leaflet extension device with an expandable member according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Figure 1 shows a mitral valve with anterior and posterior leaflets. The anterior leaflet has a semicircular shape and is attached to two-fifths of the annular circumference. The movement of the anterior leaflet defines the boundary between left ventricular inflow (diastole) and outflow (systole). The posterior leaflet of the mitral valve is crescent-shaped and is attached to approximately three-fifths of the annular circumference. The posterior leaflet typically has two clearly defined recesses that divide the leaflet into three individual scallops identified as P1 (anterior or lateral scallop), P2 (middle scallop), and P3 (posterior or medial scallop). The three corresponding segments of the anterior leaflet are A1 (anterior segment), A2 (middle segment), and A3 (posterior segment). The leaflet recesses help the posterior leaflet open during diastole.

[0015] As shown in Figure 1, the mitral valve has anterior-lateral and posteromedial commissures, which define distinct regions where the anterior and posterior leaflets meet in the annulus. While these commissures can exist as clearly defined leaflet segments, often this region is a subtle structure identifiable using two anatomical landmarks: (a) the axes of the corresponding papillary muscles and (b) the commissural chordae, which have a specific fan-shaped morphology. Several millimeters of valve tissue separate the free edges of the commissures from the annulus.

[0016] The mitral valve is an atrioventricular valve that separates the left atrium from the left ventricle. The mitral annulus defines the anatomical junction between the left ventricle and the left atrium. The fixed ends of the leaflets are attached to the annulus. The anterior portion of the mitral annulus is attached to the fibrous trigones and is generally more expanded than the posterior annulus. The right fibrous trigones are the densely junctional areas between the mitral, tricuspid, and non-coronary leaflets of the aortic annulus and membranous septum. The left fibrous trigones are located at both the left fibrous border of the aorta and the junction of the mitral valve.

[0017] The mitral annulus is less fully expanded at the insertion site of the posterior leaflet because this segment is not attached to any fibrous structures and the fibrous skeleton in this region is discontinuous. The circumference of the posterior portion of the annulus increases, which can lead to mitral regurgitation in conjunction with left atrial or left ventricular dilation. The mitral annulus is saddle-shaped, and during cardiac systole, the commissure region moves proximally, toward the superior wall of the atrium, while annular contraction also narrows the circumference. Both processes aid in leaflet coaptation and can be adversely affected by processes such as annular dilation and calcification. The mitral annulus is surrounded by several important anatomical structures, including the aortic valve, coronary sinus, and circumflex artery.

[0018] Functional cusp extension Previous approaches to addressing mitral valve annular enlargement have primarily focused on reshaping the annulus using annuloplasty rings or coapting the anterior and posterior leaflets to facilitate coaptation. These approaches may not be suitable in situations where the gap or spacing between opposing leaflets is too large. Some embodiments of the present invention provide a leaflet extension device that functionally lengthens and attaches to the natural leaflet, for example, without irreversibly destroying the leaflet (e.g., without puncturing and / or completely penetrating the leaflet), thereby allowing the leaflet extension device to be repositioned and / or removed as needed.

[0019] There have also been prior art attempts to lengthen the leaflet. Some conventional approaches utilize anchoring mechanisms that penetrate the leaflet. However, such approaches are sometimes disregarded because they do not allow for repositioning and / or retrieval of the leaflet extension device. Other approaches use leaflet extension devices, but existing leaflet extensions are invasively attached to the leaflet by anchors that penetrate the leaflet.

[0020] In contrast, the leaflet extension device of the present invention is attached atraumatically to the leaflet, eg, without penetrating the leaflet, allowing for repositioning and / or removal of the leaflet extension as needed.

[0021] 2A-2C illustrate a leaflet extension device 100 configured to be attached to the leaflets of a native heart valve. In some embodiments, the leaflet extension device 100 is configured to bridge a gap between the anterior and posterior leaflets of 3-15 mm. Additionally, the leaflet extension device is configured to be attached to the leaflet without irreversibly destroying (e.g., permanently damaging) the leaflet. This allows for the leaflet extension device to be removed and repositioned as needed.

[0022] The leaflet extension device 100 is configured to provide an artificial coaptation surface in place of one of the valve leaflets (anterior or posterior leaflet). For ease of explanation, the device 100 is described with respect to the posterior leaflet of the mitral valve, but the device 100 can be similarly utilized for the anterior leaflet of the mitral valve or the leaflets of other heart valves, such as the aortic valve or tricuspid valve.

[0023] The leaflet extension device 100 can include an expandable member 110 (shown in phantom in FIGS. 2A-2C) and a cover 130. The device 100 includes a joining portion 112, a stabilizing portion 114, and a fixation member 116. The expandable member 110 has a delivery configuration and a deployed configuration suitable for delivery through the vasculature within a catheter. In the deployed configuration, the joining portion 112 is positioned to provide an artificial joint surface for one or more native valve leaflets, and the stabilizing portion 114 and fixation member 116 are configured in combination to secure the device 100 relative to the valve anatomy. The cover 130 can be attached to or integral with the expandable member 110.

[0024] The expandable member 110 may be a mesh material, a latticework frame, and / or a frame with one or more struts, or the expandable member may include an inflatable component (e.g., a bladder / balloon) in addition to or instead of a frame. In the illustrated embodiment, the expandable member 110 has primary struts 120 (shown in phantom) and transverse struts 122 (shown in phantom). The primary struts 120 may be joined to each other at first ends 123 and extend to second ends 124 at the termination of the anchoring members 116. The primary struts 120 may be configured to fan out from the first ends 123 and bend in the deployed configuration at the regions that define the junctions 112.

[0025] FIG. 3 is a side view of a frame-type expandable member 110 without a cover 130. The primary struts 120 may extend and fan out from the hub at a first end 123, thereby forming an interior volume 132 within the interface portion 112 and the stabilizing portion 114. The primary struts 120 may, for example, bend from the stabilizing portion 114 through the interface portion 112 along a transition, and then all or a subset of the primary struts 120 may further extend from the interface portion 112 to form at least a portion of the fixation member 116. The fixation member 116 may be a clip that, in the expanded configuration, contacts the stabilizing portion 114 and exerts a tight clipping force on the natural cusp. Alternatively, the fixation member 116 may be spaced from the stabilizing portion 114 by a gap 134, as shown in FIG. 3. The transverse struts 122 may be configured to position the primary struts 120 so that the primary struts 120 retain a desired configuration after deployment.

[0026] 2A-3, the joining portion 112, the stabilizing portion 114, and the fixation member 116 are integrally formed with one another. For example, the joining portion 112, the stabilizing portion 114, and the fixation member 116 may be integrally formed with a continuous main strut 120 or a transverse strut 122 of the expandable member 110. In other embodiments, at least one of the joining portion 112, the stabilizing portion 114, and / or the fixation member 116 may be a separate component from the others, or each of the joining portion 112, the stabilizing portion 114, and the fixation member 116 may be separate from one another.

[0027] Referring to FIGS. 2A-2C, the interface portion 112 extends beyond the free ends of the leaflets, thereby providing a prosthetic interface that functionally extends the native heart valve leaflets. The interface portion 112 may have any smooth shape that mates with the opposing leaflets. While the illustrated interface portion 112 in FIGS. 2A-2C is a closed loop or ring, the present invention is not limited to the illustrated embodiment, as any smooth shape can be used. The interface portion 112 and the stabilizing portion 114 enclose a hollow interior volume 132 (FIGS. 2A and 3) that is sealed by a cover 130. After implantation, the hollow interior volume 132 of the device 100 is at least partially filled with blood, which clots and is replaced by tissue over time. This can contribute to long-term fixation of the leaflet extension device 100. The interface portion 112, in combination with the cover 130, provides an atraumatic interface for the opposing native leaflets (anterior leaflets).

[0028] When the expandable member 110 is a frame, it can include struts and / or mesh made of any biocompatible material, such as plastic, stainless steel, or a superelastic, self-expanding material, such as a nickel-titanium alloy, e.g., Nitinol®. The cover 130 can be a biocompatible fabric made of a polymer or biocompatible material, such as polyethylene terephthalate (PET), expanded polytetrafluoroethylene (ePTFE), silicone, urethane, pericardium, etc. The cover 130 can be attached to the struts 120, 122 by sutures, adhesives, sintering, and / or other suitable attachment techniques.

[0029] In operation, the fixation member 116 is biased toward the stabilizing portion 114 to clamp the natural cusp within the gap 134 between the fixation member 116 and the stabilizing portion 114 upon deployment. One aspect of some embodiments of the present invention is that the stabilizing portion 114 and the fixation member (ventricular) 116 crimp against the natural cusp without penetrating the natural cusp. The fixation member 116 may include one or more clips configured to crimp against, for example, the atrial and ventricular sides of the cusp. In the non-limiting example shown in FIGS. 2A-2C , the fixation member 116 may be a clip that abuts against the ventricular side of the natural cusp while the stabilizing portion 114 abuts against the atrial side of the natural cusp, although this configuration may be reversed if desired. In either case, the natural cusp is clamped (e.g., sandwiched) between the stabilizing portion 114 and the fixation member 116. In some embodiments, the leaflet extension device 100 is attached to the natural leaflet solely by the compressive force of the stabilizing portion 114 and the fixation member 116 without penetrating the natural leaflet.

[0030] 2A , the device 100 can further include a friction element 140, e.g., a cleat, that engages or penetrates the leaflets. The friction element 140 can extend from the stabilizing portion 114 and / or the fixation member 116. Alternatively, for example, the friction element 140 can be attached to or integrally formed with the stabilizing portion 114 and / or the fixation member 116. The friction element 140 can be sharpened to facilitate engagement with the leaflets. In some cases, the friction element 140 can penetrate into the native heart valve leaflets without completely penetrating them. In other cases, the friction element 140 can penetrate completely through the entire thickness of the native leaflets.

[0031] The leaflet extension device 100 is adapted to be delivered and implanted within a beating heart using minimally invasive techniques. For example, the leaflet extension may be delivered via a catheter using a transfemoral approach. The leaflet extension device 100 is attached to the desired leaflet using fixation members 116.

[0032] The stabilizing portion 114 and / or fixation member 116 can be sized to engage all or a portion of the natural leaflet. When they engage the entire leaflet, they can support the leaflet in a torn state. Alternatively, the stabilizing portion 114 and / or fixation member 116 can be sized to engage only a portion of the natural leaflet, such as the central scallop P2 of the posterior leaflet, thereby leaving scallops P1 and P3 in an active state. In this embodiment, P1 and P3 can freely coapt with the anterior leaflet (opposing leaflet).

[0033] FIG. 4 is a cephalad view of the device implanted within the native mitral valve from the left atrium, and FIGS. 5A-5D illustrate one embodiment of implanting a leaflet extension device 100 at the native mitral valve. The leaflet extension device 100 can be compressed into a tubular sheath for delivery via a transseptal or transatrial approach. The leaflet extension device may also be delivered via a transapical or transaortic approach. Referring to FIG. 5A, a delivery catheter 500 or sheath can be positioned within the left atrium LA above the P2 portion of the posterior leaflet PL of the mitral valve. Next, an instrument catheter 510 can be advanced through the delivery catheter 500 to position the leaflet extension device 100 (FIGS. 2A-3) at the native valve near the center of the P2 leaflet edge of the posterior leaflet PL while still contained within the instrument catheter 510, as shown in FIG. 5B. Referring to FIG. 5C, the fixation member 116 is then partially released from the device catheter 510, causing it to bend against the ventricular surface of the cusp. During this process, the physician ensures that the leaflet extension device 100 is at the appropriate height and that the fixation member 116 passes between the chordae tendineae. FIG. 5D illustrates the process after the fixation member 116 has been fully deployed and the stabilizing portion 114 has been partially deployed, causing the stabilizing portion to fan inward and outward. FIG. 5E illustrates the process after the leaflet extension device 100 has been deployed and the expansion member 110 (FIG. 3) has expanded to its deployed configuration. At this stage in the process, the posterior leaflet PL is clamped between the stabilizing portion 114 and the fixation member 116, while the anterior leaflet A1 coapts and abuts the atraumatic surface of the coaptation portion 112. Once the sheath is retracted to the atrial end of the device 100, the effectiveness of the device in reducing or eliminating mitral regurgitation can be assessed. At this stage, the leaflet extension device 100 is functionally deployed but still connected to the delivery catheter. If the device 100 is working properly, it can be removed / detached from the delivery catheter. If not, the device catheter 510 and / or delivery catheter 500 can be advanced again to straighten and compress the device 100 for removal or repositioning.

[0034] The shape of the leaflet extension device 100 can be configured to enhance its effectiveness in engaging the native posterior leaflet and / or bonding with the native anterior leaflet. FIG. 6A illustrates the leaflet extension device 100 with the stabilizing portion 114 and / or fixation member 116 configured to hold the posterior leaflet PL in approximately the natural curved shape of the native leaflet. FIG. 6B illustrates the leaflet extension device 100 with the stabilizing portion 114 and / or fixation member 116 configured to hold the native posterior leaflet PL in a relatively flattened shape. The flattened shape illustrated in FIG. 6B can position the anterior edge and chordae tendineae of the native leaflet relatively close to the anterior leaflet (not shown). The interface portion 112 can have a somewhat concave shape toward the atrial side of the posterior leaflet PL, as seen in FIG. 6B, which positions the interface surface of the interface portion 112 to interface with the native anterior leaflet. The coaptation portion 112 may have a curved or even rounded shape when viewed in cross section in FIG. 6A , or may have a somewhat straight, vertical shape, as can be seen in FIG. 6B , so that the anterior leaflet has a consistent coaptation surface across a range of leaflet heights. The specific shape of the device 100 can be modified to address different anatomical variations between patients, such as partially tethered leaflets in patients with degenerative disease or tethered leaflets in patients with mitral valve insufficiency. The shape can also be modified to achieve various types of coaptation geometries. The coaptation portion 112 can be relatively vertical. Another option is a configuration in which the anterior leaflet may close against the ventricular features of the implant, creating a “trap door” geometry.

[0035] 7A and 7B show the leaflet extension device 100 as viewed from the left atrium after implantation. The device 100 can extend approximately 25-35 mm along the edge of the posterior leaflet PL, following the curved edge of the posterior leaflet PL. The interface portion 112 can be slightly curved in the opposite direction, as shown in FIG. 7A, or can be relatively straight, as shown in FIG. 7B.

[0036] The length of the native leaflet, measured from the annulus to the leaflet edge, ranges from about 20 mm to about 30 mm. The stabilizing portion 114 of device 100 abuts the atrial surface of the posterior leaflet PL, and this stabilizing portion may be relatively straight, as shown in FIG. 7A, or the stabilizing portion 114 may be bulbous (e.g., flared) to engage / support as much surface area of ​​the native leaflet as possible, as shown in FIG. 7B.

[0037] The stabilizing portion 114 may extend beyond the fixed ends of the leaflets and partially up the atrial wall above the mitral valve annulus, as shown in FIGURE 8A. This configuration of the stabilizing portion 114 increases the longitudinal dimension of the device 100 so that it can easily expand outward and cover a greater portion of the atrial surface, further stabilizing the device 100. For example, such a long stabilizing portion 114 may stiffen the device 100 against the atrial wall and prevent the device 100 from everting into the left atrium under systolic blood pressure, thus facilitating treatment of mitral regurgitation due to posterior leaflet flutter or prolapse.

[0038] The cover 130 of the device 100 shown in FIG. 8A can promote ingrowth into the atrial wall. As a result of this ingrowth, the medial scallop P2 of the posterior leaflet can permanently assume a closed position, so that the medial scallop P2 effectively acts as a stop. The device 100 can include an anchoring mechanism (not shown), such as a screw, tack, or eyelet for a screw or tack, useful for securing the end of the stabilizing portion 114 to the atrial wall or mitral valve annulus.

[0039] The posterior leaflet of the human mitral valve typically has a gap between the posteromedial and anterolateral groups of chordae tendineae, which may be approximately 8-10 mm wide, and the fixation member 116 may be configured to be consistently positioned between the chordae tendineae (CT). Figure 9A, for example, shows the fixation member 116 of the device 100 configured to rest against the ventricular surface of the natural posterior leaflet. The fixation member shown in Figure 9A has a relatively narrow width and a pointed / rounded tip that can be predictably positioned within the gap between the chordae tendineae (CT).

[0040] 9B-9D show various embodiments of the fixation members 116 that are straight (FIG. 9B), spade-shaped (FIG. 9C), or fanned out (FIG. 9D). The wider fixation members 116 shown in FIGS. 9B-9D can help stabilize the device 100 when, for example, a portion of the posterior leaflet may flap or prolapse.

[0041] 9E, the fixation member 116 can extend into the natural alcove AA located between the ventricular wall muscle and the posterior cusp. This extension of the fixation member 116 can enhance stabilization of the device 100, which is expected to facilitate forming a firmer contact with the natural cusp and preventing it from everting upward under systolic blood pressure.

[0042] In some of the above-described embodiments, one or more of the fixation members 116 pass through the gap between the posteromedial and anterolateral groups of chordae tendineae and press against the ventricular surface of the posterior leaflet, thereby holding the implant in place. One or more fixation members 116 may also extend more medially and laterally under the posterior leaflet, passing between the chordae tendineae wherever convenient. In such embodiments, it may be necessary to expand the device 100 laterally and medially, after which such fixation members may extend between the chordae tendineae to avoid bunching in the central gap between the chordae tendineae. In some applications, it may be desirable to fold the fixation members 116 back only into the central gap between the medial and lateral groups of chordae tendineae to reduce entanglement of the fixation members 116 with the chordae tendineae.

[0043] FIG. 10A illustrates a leaflet extension device 100 having a first fixation member 116a and a second fixation member 116b. The first fixation member 116a may be substantially similar to the fixation member 116 described above with reference to FIGS. 2A-9E. The second fixation member 116b is located near the lateral and medial edges of the device; in such cases, it may be advantageous to deploy the second fixation member 116b or other ventricular elements after initial deployment of the device 100. For example, the second fixation member 116b may be advanced into the gap between the chordae after the device 100 has expanded medially and laterally. In some embodiments, the second fixation member 116b may be advanced through tubes 1005 attached to the outer and inner portions of the device 100. The tubes 1005 may be made of polyimide or the like, and may be attached to the expandable member 110 or the cover 130 of the device 100. For example, tube 1005 can be attached to expandable member 110 at the same time that cover 130 is attached, e.g., by suturing all of these elements together. It may be desirable for one or more of the struts of stabilizing portion 114 (FIGS. 2A-2C) to have a lumen sized to receive second fixation member 116b, thereby eliminating the need for tube 1005.

[0044] The second fixation members 116b may be made of a resilient material, such as a superelastic nickel-titanium alloy, such as Nitinol®, that is preformed to conform to the shape of the deployed implant so that they are biased to apply pressure to the ventricular surface of the native apex. The second fixation members 116b may further include atraumatic ends, such as paddles or loops, that have an increased surface area to maximize gripping force and reduce trauma to the native apex.

[0045] The device 100 may be easier to position within the native valve with fixation members 116 that are not a unitary series of struts that form the coaptation portion 112. Thus, the fixation members 116 may be separate struts that advance individually or together against the ventricular surface of the posterior leaflet. Figure 10B, for example, shows such a device 100 with a fixation member 116 similar to second fixation member 116B advanced through tube 1005 to be positioned against the ventricular surface of the native leaflet.

[0046] FIGS. 11A and 11B illustrate variations of an expandable member 110 suitable for use in the device 100. The expandable member 110 may be cut from a flat sheet of nickel-titanium alloy with a number of primary struts 120 and transverse struts 122. As best shown in FIG. 11A, multiple central primary struts 120 may extend serially through the stabilizing portion 114, the interface portion 112, and the fixation member 116. The stabilizing portion 114 of the struts 120 may be biased to rest against the atrial surface of the posterior leaflet, and the interface portion 112 may be configured to provide support for the artificial interface. The interface portion of the primary struts 120 may be supported by the transverse struts 122 to promote stability of the device 100. In the embodiment shown in FIGS. 11A and 11B, four primary struts are provided that are configured to rest against the atrial surface, and five primary struts 120 are configured to define the interface surface 112. The fixation structure 116 is supported by three central main struts 120 such that the fixation structure 116 extends below the ventricular surface of the posterior leaflet.

[0047] For transseptal delivery of device 100 from a femoral venous access site, the outer diameter of the entire device 100 and delivery system as a whole should not exceed 24 French (8 mm diameter), although larger diameters may be appropriate for some applications. As a result, if device 100 has nine linearly arrayed primary support struts 120, each primary support 120 may have a maximum width of, by way of non-limiting example, 0.5 mm (0.020 inch).

[0048] To achieve smaller diameters, device 100 may be constructed by cutting a cylindrical nickel-titanium alloy tube with many (perhaps 6-12) straight elements (e.g., main struts 120). These straight elements may be connected to each other by transverse struts (e.g., chevrons) or other flexible elements to provide strength, stability, and enhanced friction against the leaflet surface. Approximately half of the straight elements may define a stabilizing portion 114 that may be configured to follow the atrial surface of the posterior leaflet, and half of the straight elements may define a joining portion 112 that may be bent to create a leaflet extension shape.

[0049] 12 illustrates an embodiment of the device 100 having a somewhat flattened shape and outwardly projecting transverse struts 122 for improved fixation. In such an embodiment, the transverse struts 122 located at the edges of the device 100 further stabilize the device 100 when extended further outward and inward. In cases where portions of the posterior leaflet have flapped or where there is misalignment between the P1-P2 or P2-P3 segments of the natural leaflet, such expanded transverse struts 122 can further stabilize and align the leaflet segments.

[0050] FIGS. 13A and 13B show various views of the expandable member 110 of the device 100 with individual fixation members 116. The primary struts 120 can extend from the first end 123 through the stabilizing portion 114 and the joining portion 112, such that the primary struts 120 extend to a point below the posterior leaflet. The device 100 can have primary struts 120 with lumens through which the individual fixation members 116 can be moved from a retracted position to an extended position, allowing the individual fixation members 116 to extend from the primary struts 120 and engage the ventricular surface of the native apex, holding the implant 100 in place. The device 100 of FIG. 13A has independently advanceable fixation members 116 located at the lateral and medial edges of the implant 100. Alternatively, all of the fixation members 116 of the device 100 shown in FIG. 13B are independently advanceable. The primary struts 120 can be hollow metal or polymer tubes. In another embodiment, the device 100 shown in Figures 13A and 13B has solid primary struts 120 and separate tubes, such as polyimide tubes, attached to the primary struts. If such separate tubes are attached to the sides of the primary struts 120 that match the inner diameter of the tubes, the overall device diameter is minimized when the implant 100 is compressed for delivery. The interface portions 112 can be covered with a fabric covering, as described above.

[0051] FIG. 13B further illustrates an extension mechanism 1310 that extends and retracts the fixation members 116. The extension mechanism 1310 may include individual wires with a proximal portion 1314, a distal portion 1316, and an atraumatic tip 1318. The distal portion 1316 and tip 1318 of the wires comprise the fixation members 116. The proximal portion 1314 of each movable wire may extend proximally to the handle or may be releasably attached to a separate push wire in the delivery system, allowing for independent movement of each wire to the appropriate position. Alternatively, the extension mechanism 1310 may include a plunger 1312 to which one or more of the wires may be attached, such that all of the wires attached to the plunger can be advanced or retracted simultaneously (as shown in FIG. 13C). This simplifies the construction of the delivery catheter, speeds up the implantation process, and simplifies the release of the implant from the delivery catheter.

[0052] 14A-14D illustrate an instrument 100 having an interface portion 112 that is independently deployed relative to the stabilizing portion 114. For example, the interface portion 112 may include separate elements that are deployed by advancing the separate elements relative to elements of the stabilizing portion 114. The interface portion 112 may be adjustable such that further advancement of the interface portion relative to the stabilizing portion 114 can expand the implant 100 to further improve adhesion.

[0053] 14A and 14B illustrate some embodiments of the device 100 in which the stabilizing portion 114 and the interface portion 112 are joined at a distal region of the stabilizing portion 114. Specifically, the stabilizing portion 114 includes a first main strut 120a and an eyelet 1410 at the end of the first main strut 120a, and the interface portion 112 includes a second main strut 120b configured to pass through the eyelet 1410. The device 100 can further include cross struts 122 between the first main struts 120a of the stabilizing portion 114. The first main strut 120a of the stabilizing portion 114 may be cut and formed from a flat metal sheet (e.g., a shape memory material such as Nitinol), and the second main strut 120b of the joining portion 112 may be cut and formed from a second metal sheet (e.g., a shape memory material such as Nitinol, see e.g., Figures 14A and 14C).

[0054] Figures 14B and 14D show how the first and second main struts 120a, 120b can be configured to have curves that approximate their desired final shape in the expanded state. The device 100 shown in Figures 14A and 14B has a central second main strut 120b connected to each other at their distal ends to form the anchoring portion 116. The device 100 shown in Figures 14C and 14D has separate second main struts 120b that are curved separately from each other to form multiple anchoring members 116. The second main struts 120b of the interface portion 112 pass through openings / eyelets 1410 at the distal end of the first main strut 120a of the stabilizing portion 114. The first and second main struts 120a, 120b can be joined to each other at the proximal end of the device 100.

[0055] Once device 100 is deployed with stabilizing portion 114 bearing against the surface of the posterior leaflet and fanning outward and inward, interface portion 112 can be further advanced so that the distal extension of second major strut 120b comprising fixation member 116 folds back down against the ventricular surface of the posterior leaflet. This movement clamps device 100 in place and simultaneously lifts interface portion 112 and extends the posterior leaflet toward the anterior leaflet.

[0056] Figures 14E-14G illustrate the deployment sequence of the device 100 shown in Figures 14C and 14D. Figure 14E shows the device 100 after it has been partially exposed from the distal portion of the delivery catheter 1420. At this point, the stabilizing portion 114, the interface portion 112, and the fixation member 116 can be at least partially aligned with one another. Figure 14F shows the device 100 after the interface portion 112 has begun to flex, and Figure 14G shows the device 100 after the stabilizing portion 114, the interface portion 112, and the fixation member 116 have moved to their deployed configurations.

[0057] 15A and 15B illustrate an embodiment of a leaflet extension device 100 that may be substantially similar to any of the devices shown in and described with reference to FIGS. 2A-14G, except that the device 100 of FIGS. 15A and 15B includes an atrial stabilizer 1510. The device 100 shown in FIGS. 15A and 15B may include a stabilizing portion 114 with an eyelet 1410, a joining portion 112, and a fixation member 116. In the illustrated embodiment, the stabilizing portion 114 may include a first main strut 120a, the joining portion 112 may include a second main strut 120b that may be extendable from the first main strut 120a, and the fixation portion 116 may include a third main strut 120c. The stabilizing portion 114 and fixation member 116 may further include transverse struts 122. The interface portion 112 can slide through the eyelet 1410 to stretch the interface portion 112 and the securing member 116 relative to the stabilizing portion 114 as described above with reference to Figures 14A-14G.

[0058] The atrial stabilizer 1510 is configured to engage the atrial wall of the heart. While the atrial stabilizer 1510 is illustrated as a rectangular element surrounding an opening 1520, the atrial stabilizer 1510 may be a single strut or series of struts, or may be any polygonal, circular, oval, elliptical, or other shape suitable for engaging the atrial wall. In use, the atrial stabilizer 1510 is configured to contact or otherwise engage the atrial wall, and the atrial stabilizer 1510 may include frictional elements, such as cleats and / or a fabric covering. The atrial stabilizer 1510 may further include a fabric covering to promote tissue ingrowth and / or encapsulation, which may provide additional long-term fixation for the leaflet extension device 100.

[0059] 15A and 15B is configured to be deployed with the stabilizing portion 114 bearing against the atrial surface of the posterior leaflet and fanning outward and inward. Advancement of the commissure portion 112 causes the fixation members 116 to fold back against the ventricular surface of the posterior leaflet, thereby clamping the device in place while simultaneously lifting the commissure portion 112 and extending the posterior leaflet toward the anterior leaflet.

[0060] The device 100 shown in and described above with reference to Figures 14A-15B may have additional features directed to specific functions. For example, advancing the interface portion 112 relative to the stabilizing portion 114 simultaneously deploys frictional elements, barbs, chevrons, or anchors formed with and / or on the stabilizing portion 114. For example, advancing the interface portion 112 forces such frictional elements downward against, into, or through the atrial surface of the natural cusp. The device 100 may further include locking elements (not shown) that lock the interface portion 112 in a particular position relative to the stabilizing portion 114. For example, the device may have locking tabs or elements that are selectively deployed with more or less extension against the natural cusp. Additionally, the relative thicknesses of the stabilizing portion 114, interface portion 112, and fixation member 116 at various points along their lengths may be varied to achieve a desired range of shapes based on the degree of deployment. In an alternative configuration, the joint portion 112 may have separate second major struts 120b that are individually advanceable to adjust the relative extension of the device 100 along the joint line.

[0061] FIG. 16 illustrates a leaflet distraction device 100 having an expandable member 110 that includes an inflatable balloon or bladder 1610. The inflatable balloon or bladder 1610 can be used with any of the leaflet distraction devices 100 shown in and described above with reference to FIGS. 2A-15B, either in addition to or instead of a frame with one or more primary and / or transverse struts. Once the device is in place at the native valve, the inflatable bladder 1610 can be inflated. The bladder 1610 can have a joining portion 112 configured to face the opposing leaflet so that the bladder 1610 joins the opposing leaflet. The bladder 1610 can be inserted into the hollow interior volume 132 (FIG. 2A) that is surrounded by the joining portion 112 and stabilizing portion 114 shown in and described above with reference to FIG. 2A. Inflating the bladder 1610 pushes the coaptation portion 112 toward the opposing cardiac valve leaflet (e.g., the anterior leaflet). The bladder 1610 can be inflated as needed to allow coaptation with the native anterior leaflet and eliminate insufficiency.

[0062] Leaf extension with actively displaceable base member 17A-17D illustrate an exemplary leaflet extension device 1200 having two members 1702, 1704. Member 1702 has a first end 1702A and an opposite second end 1702B. Member 1704 has a first end 1704A and an opposite end 1704B. Second end 1702B is attached to first end 1704B using conventional attachment methods, including screws, rivets, and the like. Members 1702, 1704 can be formed from any biocompatible material, including plastic, metal, and the like. For example, members 1702, 1704 can be made from stainless steel, a nickel-titanium alloy, such as Nitinol®, or a cobalt-chromium-nickel-molybdenum alloy, such as Elgiloy®. Members 1702, 1704 may be made from a solid sheet of material, a mesh, one or more struts, a latticework frame, or the like.

[0063] Member 1702 has a first face 1702F and an opposite second face 1702G. Member 1704 has a first face 1704F and an opposite second face 1704G. First face 1702F of first member 1702 abuts first face 1704F of second member 1704. First end 1704A of second member 1704 is not attached to first member 1702 and is elastically displaceable relative to first member 1702.

[0064] The first member 1702 and the second member 1704 cooperate to sandwich and grip the first native leaflet without penetrating it. The first and / or second members may have frictional engagement elements that can frictionally engage (move into) the native heart valve leaflet without penetrating it, or the frictional engagement elements may puncture into, but not penetrate, the native heart valve leaflet.

[0065] The leaflet extension device 1700 has an interface element 1703 attached to the second face 1702G of the first member 1702. The interface element 1703 may have a teardrop shape and may have a convex portion 1703C extending beyond the second end 1702B, and the interface element 1703 preferably has a smooth outer surface that interfaces atraumatically with the second natural leaflet (not shown).

[0066] The joint element 1703 can be made of a biocompatible foam that may or may not have an internal framework. Alternatively, the joint element 1703 can be formed of a framework 1708 made of one or more interconnected struts or meshes. The framework 1708 encloses a hollow interior volume that is sealed by a fabric covering 1710.

[0067] A tether 1712 is operatively connected to the first and second members 1702, 1704. In some embodiments, the tether 1712 is used to actively displace the second member 1704 relative to the first member 1702. The tether can be made of a variety of biocompatible materials, including metal wire, such as stainless steel, polymer sutures made from expanded polytetrafluoroethylene (ePTFE), ultra-high molecular weight polyethylene (UHMWPE), or polyester.

[0068] First member 1702 and / or second member 1704 may be made of a superelastic alloy that elastically deforms from a native shape to a deformed shape in response to an external force, but returns to its native shape once the external force is removed, and pulling on tether 1712 causes second member 1704 to elastically displace relative to first member 1702.

[0069] An atrial stabilization member 1718 may be provided at the end 1702A-1 of the first member 1702, which may be attached to a wireform that helps provide atrial stabilization.

[0070] Leaf extension with expandable member In some cases, it may be desirable to increase the effective clamping force. Adding an expandable element between the native leaflet and either the fixation member 116 or the stabilization portion 114 can increase the effective clamping force on the leaflet and improve the fixation of the leaflet extension device 100. For example, FIGS. 18A-18C show a device having an expandable element 1810. While the expandable element 1810 can be placed on the atrial side of the leaflet, the present invention focuses on adding the expandable element 1810 between the fixation member 116 of the leaflet extension device and the ventricular surface of the native heart valve leaflet. Placing the expandable element under the leaflet can limit movement of the device and provide a more stable structure against which the opposing leaflets abut as closure occurs.

[0071] For example, the expandable element 1810 can also limit leaflet movement by interfering with the leaflet's ability to fully open. The expandable element 1810 can expand toward the ventricular wall, causing the expandable element to contact the ventricular wall intermittently or continuously throughout the cardiac cycle. This can be advantageous for a number of reasons. This can stabilize the device 100 and / or the leaflets, thereby reducing excessive movement and any wear, stress, or damage to the implant, the clipped leaflet, the anterior leaflet, or adjacent leaflets.

[0072] The expandable element 1810 can potentially reduce insufficiency in the repaired valve in a variety of ways. The expandable element can improve the ability of the leaflet extension device 100 to coapt with the opposing leaflet by pushing the leaflet extension device 100 toward the opposing leaflet. The expandable element can also improve the ability of the adjacent leaflet, for example the P1 and P3 leaflets of the posterior leaflet, to coapt by either holding the P2 leaflet in a better position or by creating a surface against which the P1 and P3 can coapt.

[0073] 18A-18C show examples of expandable element 1810 in cross section. FIG. 18A shows device 100 when initially positioned, and FIGS. 18B and 18C show device 100 after expansion of expandable element 1810. The cross-sectional shape of expandable member 1810 can have various contours, as shown in the difference between FIGS. 18B and 18C. For example, the natural cusp can be held in a flattened or curved shape, the expandable element 1810 can be generally round, triangular, or polygonal in cross section, and the expandable element 1810 may or may not expand toward the ventricular wall.

[0074] In addition to the cross-sectional profile of the expandable element 1810, the profile of the expandable element 1810 in other dimensions is equally important. For example, the fixation member 116 may have a relatively narrow distal profile to facilitate placement in the untethered region of the posterior leaflet. When the expandable element 1810 is expanded between the fixation member 116 and the ventricular surface of the apex, the distal end of the expandable element 1810 may be wide so that it contacts the ventricular surface of the apex, as shown in FIGS. 18B and 19 . This may give the expandable element 1810 a somewhat triangular profile facing the ventricular wall. Nearer the apical edge, the fixation member 116 may be approximately as wide as the untethered zone of the apex, and the expandable element 1810 may be as wide or slightly wider.

[0075] As described above, the expandable element 1810 can extend posteriorly so that it constantly touches or presses against the ventricular wall. Alternatively, the expandable element can be designed to minimize contact with the posterior wall, thereby leaving at least some range of motion available for the posterior leaflet. This can allow the posterior leaflet to open somewhat during diastole, thereby reducing potential gradients in the mitral valve. Such a shape can also help push the leaflet and implanted device out of the way and against the ventricular wall if a prosthetic mitral valve needs to be implanted later.

[0076] The expandable element 1810 can also be designed to expand outward under the ventricular side of the native leaflet cusps P1 and P3. The outward extensions of the expandable member 110 can span any gaps between P1 and P2 or between P2 and P3. They can also hold P1 and P3 in a generally closed position in alignment with the P2 leaflet. However, there may be strut chords, tertiary tendons, or even primary tendons that tend to obstruct the expansion of these outward extensions. Therefore, these outward extensions can be designed to be very low pressure, highly expandable balloon elements that can expand around and between the tendons, or they can be multiple finger-like extensions that extend between the tendons, as shown in FIG. 20.

[0077] The expandable element 1810 itself may comprise an inflatable balloon or bladder that may be configured to expand to a particular size and shape to achieve the particular design objectives described above. Alternatively, the expandable element may be an expandable elastic balloon that expands to a more spherical shape until it is constrained by the remainder of the device, by tendons or valve leaflets, or by the ventricular wall.

[0078] Rigid or semi-rigid elements may also be attached to the expandable element 1810. Referring to FIG. 21 , the device may have frictional elements 2114, such as bumps, spikes, or other features, that enhance frictional engagement with the valve leaflets. Alternatively, the frictional elements 2114 may be rigid or semi-rigid linear elements that constrain the expandable element 1810 to one of the potential shapes discussed above, such as a triangular, prismatic, or polyhedral shape. For example, the expandable element 1810 may have rigid linear elements attached to its surface that appose the ventricular surface of the leaflet and help it securely engage the leaflet region. When the expandable element 1810 is collapsed for delivery, these elements align with the fixation members 116 to minimize the delivery profile. These rigid linear elements may also have ridges, grooves, bumps, spikes, or other features that further enhance frictional engagement with the surfaces of the valve leaflets.

[0079] The expandable element 1810 can be a balloon or bladder made of a biocompatible material, such as urethane, expanded PTFE, polyester, polyolefin, or other materials, or combinations thereof. For example, the bladder can have an expanded PTFE outer surface for optimal tissue ingrowth and tissue compatibility at the interface, and an inner layer of urethane to seal the bladder for leak-free inflation.

[0080] During delivery, the expandable element 1810 may be delivered with an inflation tube inserted for inflation. The inflation tube extends up through the delivery catheter of the device. Once the expandable element 1810 is inflated to a desired shape or volume, the tube can be retracted so that the expandable element 1810 remains permanently inflated to that size.

[0081] The expandable element 1810 can be inflated with one or more polymers that crosslink or harden over a period of time, resulting in a permanent bladder shape. Examples of such polymers include polyethylene glycol, silicone, methacrylate, and others. The expandable element 1810 can also be filled with a coiled and / or braided structure made of a biocompatible material. These coils can be similar to those used for intravascular coiling. Alternatively, the expandable element 1810 can be inflated with saline or other biocompatible solution that remains permanently liquid. Thus, if it is desired to deflate the expandable element 1810 in the future, for example to make room for the implantation of a prosthetic mitral valve, this can be accomplished by puncturing the bladder with a needle and rupturing it. This can be performed using interventional catheter techniques.

[0082] Alternatively, the expandable element 1810 may be made of an elastomeric material or an expandable mechanical structure. For example, the expandable element 1810 may be an additional superelastic frame, braid, coil, or mesh. This allows the expandable element to collapse into a low-profile shape for delivery, and then the expandable element self-expands once in place. The braid or mesh structure may be made of stainless steel or a cobalt-chromium-nickel-molybdenum alloy (e.g., Elgiloy®). Such an expandable element 1810 may have openings that allow the interior volume to fill with blood during or after expansion.

[0083] The above-described embodiments have described an implantable leaflet extension device with a fixation and stabilization element made of a superelastic nickel-titanium alloy (e.g., Nitinol®) frame that can fold back around the edges of the valve leaflets. Alternatively, the frame can be made of stainless steel, cobalt-chromium steel, a "superalloy" consisting of 39-41% cobalt, 19-21% chromium, 14-16% nickel, 11.3-20.5% iron, 6-8% molybdenum, and 1.5-2.5% manganese, such as Elgiloy®, or other biocompatible metals or metal alloys that are stronger and stiffer than Nitinol®, but do not exhibit nearly the same superelastic properties. When the leaflet extension device 1300 is made of these metals, it has enough elasticity to fan outward, but not enough elasticity to fold back around the edges of the leaflets. Thus, such devices with non-superelastic frames may be preformed into a U-shape so that they can be hooked under the posterior leaflet as shown in Figure 22. Such devices may also be formed into a "V" shape with sharp edges rather than curved edges along the edge of the extended leaflet. Such designs do not necessarily enclose a blood-filled volume.

[0084] The open end 2212 of the U can have a 3-5 mm opening large enough to hook the leaflet. Once the device is in place, an expandable element, as described above, can be inflated or expanded to clamp the leaflet. Even if the leaflet extension device 100 does not appear to adequately reduce valvular insufficiency, the device 100 can be pushed away from the posterior leaflet and placed back into the delivery sheath. The 3-5 mm opening will be small enough that the proximal end of the hook can be captured by the open end of the sheath. In this case, the sheath will compress the outwardly expanded leaflet extension as it is advanced over the device.

Claims

1. 1. A valve repair device comprising: an expandable member comprising a frame having a plurality of joined struts defining a hollow volume, the expandable member comprising a first portion configured to interface with a first native cusp of the heart valve and a second portion configured to abut an atrial side of at least a portion of a second native cusp of the heart valve; the valve repair device further includes a clip extending from the second portion of the expandable member, the clip configured to abut a ventricular side of at least a portion of the second native cusp of the heart valve to clamp the portion of the second native cusp between the second portion of the expandable member and the clip to secure the expandable member to the second native cusp; A valve repair device wherein the expandable member includes an inflatable bladder in addition to or instead of the frame.

2. The valve repair device of claim 1 , wherein the portion of the second native leaflet is a central portion of the second native leaflet.

3. 2. The valve repair device of claim 1, wherein the heart valve is a mitral valve, the second native leaflet is a posterior leaflet of the mitral valve, and the portion of the posterior leaflet is a mid-scallop P2 of the posterior leaflet.

4. 4. The valve repair device of claim 3, wherein the first native leaflet is the anterior leaflet of the mitral valve, and the expandable member is dimensioned to coapt at least one scallop of the posterior leaflet with the anterior leaflet.

5. 10. The valve repair device of claim 1, wherein the heart valve is a mitral valve, the first native leaflet is the anterior leaflet of the mitral valve, and the second native leaflet is the posterior leaflet of the mitral valve.

6. 10. The valve repair device of claim 1, further comprising a cover covering the frame along at least the first portion of the expandable member, the cover configured to provide an atraumatic interface for the first native leaflet along the first portion of the expandable member.

7. The valve repair device of claim 1 , further comprising a cover covering at least a portion of the clip.

8. The valve repair device of claim 1 , further comprising a plurality of friction elements extending from the second portion of the expandable member.

9. The valve repair device of claim 8 , wherein the plurality of friction elements are sized to penetrate into the atrial side of the second native leaflet without completely penetrating the second native leaflet.

10. The valve repair device of claim 8 , wherein the plurality of friction elements are sized to penetrate the atrial side of the second native leaflet and completely penetrate the second native leaflet.

11. The valve repair device of claim 1 , further comprising a plurality of friction elements extending from the clip.

12. 12. The valve repair device of claim 11, wherein the plurality of friction elements are sized to penetrate into the ventricular side of the second native leaflet without completely penetrating the second native leaflet.

13. The valve repair device of claim 1 , wherein the clip is separate from and coupled to the expandable member.

14. The valve repair device of claim 1 , wherein the clip is integrally formed with the expandable member.

15. The valve repair device of claim 1 , wherein the clip is actively displaceable relative to the second portion of the expandable member.

16. The valve repair device of claim 1 , wherein the clip is biased toward the second portion of the expandable member.

17. 1. A valve repair device comprising: an expandable member comprising a frame having a plurality of joined struts defining a hollow volume, the expandable member comprising an interface portion configured to interface with a first native cusp of the heart valve and a stabilizing portion configured to abut an atrial side of at least a portion of a second native cusp of the heart valve; the valve repair device further comprises a fixation member extending from the stabilizing portion of the expandable member, the fixation member configured to abut a ventricular side of at least a portion of the second native cusp of the heart valve to clamp the portion of the second native cusp between the stabilizing portion of the expandable member and the fixation member to secure the expandable member to the second native cusp; A valve repair device wherein the expandable member includes an inflatable bladder in addition to or instead of the frame.

18. 18. The valve repair device of claim 17, wherein the fixation member is separate from and coupled to the expandable member, and the fixation member is actively displaceable relative to the stabilizing portion of the expandable member.

19. 1. A valve repair device for treating a mitral valve, comprising: an expandable member comprising a frame having a plurality of joined struts defining a hollow volume, the expandable member comprising a first portion configured to contact the anterior leaflet of the mitral valve and a second portion configured to abut an atrial side of at least a portion of the posterior leaflet of the mitral valve; the valve repair device further includes a clip extending from the second portion of the expandable member, the clip configured to abut a ventricular side of at least a portion of the posterior leaflet of the mitral valve to clamp the portion of the posterior leaflet between the second portion of the expandable member and the clip to secure the expandable member to the posterior leaflet; A valve repair device wherein the expandable member includes an inflatable bladder in addition to or instead of the frame.

20. 20. The valve repair device of claim 19, wherein the clip is separate from and coupled to the expandable member, and the clip is actively displaceable relative to the second portion of the expandable member.

Images