Method and apparatus for therapy of mitral valve

Devices and methods are described for treating a mitral valve defect. The device described includes features that allow the device to conform to the actual pathology of the valve, rather than attempting to replicate a healthy valve (which the patient does not have). In this way, the device allows the patient's actual value to work as well as possible, given the valve's diseased condition. The actual pathology of the valve is accommodated by providing for multiple dimensions of adjustability of the device, including adjustability of the size (e.g., diameter) of the device as well as adjustability of the elevation or inclination of one portion of the device (e.g., the portion supporting the posterior leaflet) with respect to another portion of the device.

FIELD OF THE INVENTION

The present invention relates generally to methods and apparatuses for treating the mitral valve of the heart. More specifically, methods and apparatuses are described for treating stenosis and/or regurgitation of the mitral valve.

BACKGROUND

The heart is an organ made up mostly of muscle tissue that is responsible for circulating oxygenated blood through an organism's blood vessels using regular, repeated contractions. To facilitate the flow of blood in one direction into the heart, through its various chambers, and out to the rest of the body, the mammalian heart has four valves: the tricuspid valve, the pulmonary valve, the mitral valve, and the aortic valve. In some cases, one of the valves may not function properly, such as due to a congenital defect or disease. The mitral valve, for example, which is responsible for allowing blood to flow from the left atrium of the heart to the left ventricle of the heart, in some cases may not fully open (known as stenosis). As a result, the amount of blood flowing through the heart is decreased, which can lead to serious complications such as atrial fibrillation, blood clots, and lung congestion, heart enlargement, and heart failure, among others. In other cases, the mitral valve may not fully close (known as regurgitation or leakage). In these cases, blood from the left ventricle may leak back into the left atrium, which may lead to problems such as atrial fibrillation, blood clots, infections, and heart failure, among others.

SUMMARY

Accordingly, a method and apparatus are provided for repairing a mitral valve in a way that may have improved safety, robustness, and simplicity for administering to a patient. A device for treating the mitral valve defect is provided that includes a frame comprising an adjustable member and a fixed member, where the frame defines a conformable shape of the device. Each connected end of the adjustable member may be engaged with a corresponding end of the fixed member, and a distance measured along the adjustment member from one connected end to the other connected end may be configured to be adjustable, such that a perimeter of the shape defined by the frame is adjustable. The device may be configured to be positioned proximate a base portion of a mitral valve and adjusted to conform to a shape of the mitral valve being treated so as to improve opening or closure of the mitral valve.

In some cases, each of the fixed member and the adjustable member may define a lumen, and the frame may further comprise a cinching member extending through the respective lumens of the fixed member and the adjustable member. The cinching member may be movable with respect to the fixed member and the adjustable member to adjust the perimeter of the shape. The adjustable member may comprise two free ends that are configured to be moved with respect to each other in response to a corresponding movement of the cinching member. For example, the cinching member may comprise two slotted ends disposed within the fixed member, and the device may further comprise an adjustment mechanism configured to be actuated by a user (e.g., the surgeon) to engage the slotted ends of the cinching member and move the slotted ends with respect to each other to adjust the length of the adjustable member. The adjustment mechanism may comprise a gear configured to be rotated solely in a first direction when the gear is in a first axial position and further configured to be rotated in a second direction when the gear is in a second axial position.

In some embodiments, the device may comprise an outer covering surrounding the frame. The outer covering may comprise at least one of a polymer material or polyester. The frame may comprise nitinol.

In some embodiments, the frame may comprise at least one hinge proximate adjoining ends of the adjustable member and the fixed member. The at least one hinge may be configured to allow adjustment of an elevation of the frame with respect to a reference plane passing through the fixed member. The at least one hinge may comprise a first hinge portion connected to an end of the fixed member and a second hinge portion connected to a corresponding end of the adjustable member, and the second hinge portion may be configured to be unlocked from the first hinge portion upon receipt of a pinching force applied by a user to the at least one hinge, thereby allowing adjustment of the elevation of the frame. The at least one hinge may be configured to allow adjustment of the elevation to an angle between approximately 0° and approximately 20°.

In some cases, the frame may comprise a predefined saddle shape. In still other cases, the frame may comprise a malleable material.

In other embodiments, a method for treating a mitral valve defect is provided that comprises providing a device having a frame comprising an adjustable member and a fixed member and placing the device proximate a base portion of a mitral valve to be treated. Each connected end of the adjustable member may be engaged with a corresponding end of the fixed member, and a distance measured along the adjustable member from one connected end to the other connected end may be configured to be adjustable, such that a perimeter of a shape defined by the frame is adjustable. The device may be adjusted by adjusting the perimeter of the shape defined by the frame so as to allow the device to conform to a shape of the mitral valve being treated for improving opening or closure of the mitral valve.

Adjusting the size of the device may, in some cases, comprise actuating an adjustment mechanism of the frame. The adjustment mechanism may be configured to engage slotted ends of a cinching member extending through the fixed member and the adjustable member, and actuation of the adjustment mechanism may serve to move the cinching member with respect to the fixed member and the adjustable member. Adjusting the size of the device may comprise enlarging the size of the device by applying an axial force to the adjustment mechanism while actuating the adjustment mechanism. The frame may comprise at least one hinge proximate adjoining ends of the adjustable member and the fixed member, and the method may further comprise adjusting an elevation of the frame with respect to a reference plane passing through the fixed member by actuating the at least one hinge.

Actuating the at least one hinge may comprise applying a pinching force to the at least one hinge, and the at least one hinge may be configured to allow adjustment of the elevation to an angle between approximately 0° and approximately 20°.

In some cases, the frame may comprises a malleable material, and the method may further comprise adjusting an elevation of the frame with respect to a reference plane passing through the fixed member by applying pressure to portions of the frame.

DETAILED DESCRIPTION

Some embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the invention are shown. Indeed, various embodiments of the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout. Although the examples described herein refer to mitral valve defects such as stenosis and regurgitation, embodiments of the described invention may be used to treat various mitral valve defects affecting the proper opening and/or closure of a mitral valve, both congenital and developed due to disease or other environmental factors.

With reference toFIG. 1, the path of circulation of blood through the heart10will be described. In the human body, deoxygenated blood enters the right atrium15of the heart10via the superior vena cava20(from the upper half of the body) and the inferior vena cava21(from the lower half of the body). Once the right atrium15is full of blood, the pressure difference between the right atrium and the right ventricle25causes the tricuspid valve30to open, allowing blood to flow into the right ventricle25. As the right ventricle25contracts, blood is pushed through the pulmonary valve35and into the lungs via the pulmonary artery40, where the blood is re-oxygenated. Oxygenated blood from the lungs can then re-enter the heart10via the pulmonary veins45into the left atrium50. The pressure differential between the left atrium50and the left ventricle55when the left atrium fills with blood then causes the mitral valve60to open, and blood is allowed to flow from the left atrium to the left ventricle. Finally, contraction of the left ventricle55forces the aortic valve65to open and pushes blood into the aorta70, from which oxygenated blood is circulated through the vasculature.

Unlike the other heart valves30,35, and65, which are tricuspid valves having three leaflets, the mitral valve60is a bicuspid valve having two leaflets—the anterior leaflet62and the posterior leaflet63(shown inFIG. 2). The leaflets62,63are connected by a fibrous ring called the mitral annulus85. When the left ventricle55contracts to pump blood into the aorta, the annulus85also contracts to reduce the area of the valve and facilitate complete closure of the leaflets62,63in a healthy subject.

Small fibrous strings or cords called chordae tendineae run from the leaflets62,63to the walls of the left ventricle55. When the left ventricle55contracts, the pressure in the left ventricle is much greater than the pressure in the left atrium50, and the leaflets62,63of the mitral valve60thus have a tendency to evert (e.g., be pulled into the left atrium). When this happens, the chordae tendineae become tense and pull on the leaflets62,63, thereby preventing eversion and holding the leaflets in a closed position.

Proper functioning of the valves30,35,60, and65is essential to proper blood flow through the heart10. In some cases, however, whether due to congenital defects or disease, one or more of the valves may not open or close as it should. For example, the mitral valve60may suffer from stenosis, or a narrowing of the valve that keeps the valve from fully opening to allow blood to flow into the left ventricle55. In other cases, the mitral valve60may not fully close (referred to as leakage or regurgitation). Both conditions are undesirable and can cause serious consequences to the body, such as atrial fibrillation, blood clots, and heart failure, among others.

Conventional methods of treating mitral valve problems (e.g., stenosis and regurgitation) range from medication to surgery. If the damage done to the mitral valve and the surrounding heart tissue by the defect is not severe enough to require valve replacement, the existing mitral valve may be repaired using surgical techniques. Typically, open-heart surgery is required to perform mitral valve repairs. During this type of surgery, the patient is placed on a heart-lung machine, and the heart may be cooled to slow or stop the heartbeat. Depending on the particular type and extent of the defect, the surgeon may reshape the valve by removing excess valve tissue, add support to the annulus85by adding tissue or other structure to the valve base, or attach the valve to nearby cord tissues.

In particular, cases in which the annulus85requires additional support to allow the leaflets62,63to open and close properly are often addressed by sewing an annuloplasty ring to the valve base. Conventional rings may be made of metal, cloth, or tissue and may have a predefined size and/or shape. Thus, a surgeon must select a type and size of ring that the surgeon believes will produce the best results in the patient based on what is known about the anatomy of the mitral valve and its surroundings and the type and extent of the defect.

Accordingly, embodiments of the present invention provide an adjustable device for treating a mitral valve defect. In particular, embodiments of the device are configured to allow a size of the device (e.g., as defined by the perimeter of the device) to be adjusted (e.g., made larger or smaller) by a surgeon during a mitral valve repair procedure so as to achieve optimal results considering the actual mitral valve anatomy and the type and extent of the defect. Moreover, embodiments of the device may allow a surgeon to adjust a shape of the device to accommodate the actual shape of the patient's mitral valve and annulus, such as to adjust an elevation and/or curvature of the device as described below. In this way, the surgeon can configure the device in three dimensions (e.g., along the x-, y-, and z-axes) to achieve an optimal fit with the patient's mitral valve and maximize the support provided to the valve leaflets to effect better performance of the patient's valve. Embodiments of the device may also allow for adjustments to be made post-operatively. In other words, the device can be configured to fit with the valve in the particular patient's condition to allow the patient's valve to work as well as possible, recognizing that the patient's valve is not a healthy valve and is not functioning as a healthy valve.

With reference toFIGS. 3 and 4, a device100is provided comprising a frame110that includes an adjustable member120and a fixed member130. The adjustable member120may define two ends122,124, and the fixed member130may define two ends132,134. Each end122,124of the adjustable member120may be engaged with a corresponding end132,134of the fixed member130to form a closed shape, such as an oval, as shown. Moreover, at least one end122,124of the adjustable member120may be configured to be adjustably received by the corresponding end132,134of the fixed member130, such that a perimeter of the closed shape defined by the frame110(e.g., the circumference of the oval) is adjustable. In other words, one or both ends122,124of the adjustable member120may be received by the corresponding end132,134of the fixed member130to varying extents such that the perimeter may be decreased or increased, as needed to fit the opening of the patient's valve.

For example, referring toFIGS. 5A and 5B, the fixed member130may comprise a tubular member defining a channel136therethrough, and the at least one end122,124of the adjustable member120may be configured to be adjustably received within the corresponding end132,134of the tubular member via the channel. By moving one or both ends122,124of the adjustable member120farther into the channel at the corresponding end132,134of the tubular component of the fixed member130, the surgeon can make the perimeter of the frame110smaller. Conversely, by withdrawing the respective end122,124out of the corresponding end132,134of the fixed member130, the surgeon can make the perimeter of the frame110larger. In this way, the device may be configured to be positioned proximate a base portion of a mitral valve, and a perimeter of the device may be configured to be adjusted to fit the mitral valve being treated so as to improve the opening and/or closing of the mitral valve. In some embodiments, the fixed member130and the adjustable member120may both be tubular, so as to provide a tube-within-a-tube structure, whereas in other embodiments the adjustable member120may be a wire or other solid component (e.g., lacking a lumen) that is received by the fixed member.

Several mechanisms may be used to allow the size of the device100to be adjusted (e.g., made smaller or larger). In some embodiments, for example, a ratchet-mechanism may be used to engage the ends122,124of the adjustable member120with the corresponding ends132,134of the fixed member130. Referring toFIG. 5A, for example, one or both ends122,124of the adjustable member120may define a number of teeth300, and the corresponding end132,134of the fixed member130may define a pawl310that is configured to engage the teeth to hold the adjustable member in place. As the end122,124of the adjustable member120is pushed into the corresponding end132,134of the fixed member130(e.g., to make the device smaller), the pawl310may ride up a sloped surface of the engaged tooth300to engage the next adjacent tooth. At the same time, however, the pawl310may prevent the end122,124from being pulled out of the corresponding end132,134of the fixed member when engaged with the teeth300, locking the adjustable member120and the fixed member130in position with respect to each other.

To enlarge the size of the device100, an unlocking surface320may be pressed by the surgeon (e.g., through an outer covering of the device, described below), which may serve to push the pawl310out of engagement with the teeth300and allow the surgeon to pull the end122,124of the adjustable member120out of the corresponding end132,134of the fixed member130.

Alternatively, with reference toFIG. 5B, a plunger330may be provided that is configured to move into and out of engagement with the teeth300, such as in a direction perpendicular to a longitudinal axis of the end122,124of the adjustable member. The plunger330may be manipulated by the surgeon during placement of the device100, such as through an outer covering of the device or via an extension (not shown) protruding out of the covering that the surgeon can grip and manipulate.

In still other embodiments, the device100may include one or more adjustment ports350,352,354, shown inFIG. 9. Two of the adjustment ports352,354may be located, for example, at commissures of the device (e.g., proximate the interface between the ends122,124of the adjustable member120and the corresponding ends132,134of the fixed member130) and may be configured to receive a tool (e.g., an Allen wrench-type tool) for incrementally adjusting the size of the device100to make the device larger or smaller. The adjustments may be made, for example, via an internal gear (not shown) that is engageable by the tool via the ports352,354and that, in turn, engages ratcheted surfaces of respective ends122,124,132,134of the adjustable and fixed member120,130, such that turning the tool (and, thus, the gear) in one direction (e.g., clockwise) serves to draw the respective adjustable end122,124into the corresponding fixed end132,134, making the device smaller, and turning the tool in the other direction (e.g., counterclockwise) serves to push the respective adjustable end out of the corresponding fixed end, making the device larger.

In this regard, anterior zones A1, A2, A3and posterior zones P1, P2, P3of the opening defined by the device100may be defined, as illustrated inFIG. 9, and adjustment of the size via one of the adjustment ports352,354may serve to adjust a relative area of one or more of the zones proximate that particular port. For example, an adjustment made via the adjustment port352may serve to increase or decrease (depending on the direction in which the tool is turned) the area of posterior zone P1, while anterior zones A1, A2, and A3and posterior zones P2and P3remain relatively unchanged. Similarly, adjustment of the adjustment port354may serve to increase or decrease (depending on the direction in which the tool is turned) the area of posterior zone P3, while anterior zones A1, A2, and A3and posterior zones P2and P1remain relatively unchanged. Moreover, removal of the tool from engagement with the respective adjustment port352,354may lock the relative positions of the adjustable member120and the fixed member130with respect to each other, such that no further changes in the size of the device occur.

A third adjustment port350may also be provided at a central location of the adjustable member120, as shown inFIG. 9. In embodiments in which a third adjustment port350is provided, the adjustable member120may comprise a first portion and a second portion (not shown), and the first and second portions may have engaging ends that meet near the location of the third adjustment port350(e.g., halfway between the commissures). In this regard, the third adjustment port350may be configured to draw one or the other of the first and second portions towards the port to make the device100smaller or to push one or the other of the first and second portions away from the port to make the device larger. Accordingly, a pair of internal gears (not shown) may be provided as described above with respect to the adjustment ports352,354of the commissures that are configured to engage ratcheted surfaces of the ends of the two portions. The engagement may occur in a manner such that twisting a tool configured to engage at least one of the internal gears via the adjustment port350in one direction (e.g., clockwise) may serve to adjust one of the portions (e.g., the portion of the adjustable member120associated with the size of posterior zones P3and P2) while leaving the other portion of the adjustable member unaffected. Similarly, twisting the tool via the adjustment port350in the other direction (e.g., counterclockwise) may serve to adjust the other of the portions (e.g., the portion of the adjustable member120associated with the size of posterior zones P1and P2) while leaving the other portion of the adjustable member unaffected. This may be accomplished, for example, via one or more gears that are only configured to engage other gears or ratcheted surfaces in one direction (e.g., slipping off and not engaging the gears or surfaces when moved in the non-engaging direction).

In still other some embodiments, the at least one end132,134of the fixed member130that is configured to adjustably receive the corresponding end122,124of the adjustable member120may comprise a filling, and the filling may be configured to resist movement of the adjustable member with respect to the tubular member. For example, the channel136of the tubular member may be filled with a polymer at one or both ends132,134, such that although a surgeon may be able to push the respective end122,124of the adjustable member120into or pull the end out of the corresponding end132,134of the tubular member, the polymer filling may substantially prevent the respective engaged ends from moving with respect to each other when no force is being applied. In this way, once the surgeon has adjusted a size of the device according to the patient's anatomy and specific needs, the frame110will have a tendency to remain in the adjusted configuration and will not change sizes again without further intervention by the surgeon.

Although the depicted embodiment ofFIGS. 3 and 4shows a fixed member130that is tubular, in other embodiments the fixed member may have other configurations. For example, the fixed member may have discrete tubular portions proximate the two ends132,134within which the corresponding ends122,124may be received. As another embodiment, the fixed member may comprise a plurality of rings or other arched members extending along the perimeter of the fixed member at least in the vicinity of each end132,134through which the corresponding ends122,124of the adjustable member may be received.

In other embodiments, the fixed member130and the adjustable member120may be configured such that the adjustment in the size of the device occurs through the movement of free ends of the adjustable member120rather than at the junction between the ends122,124of the adjustable member120and the ends132,134of the fixed member130. With reference toFIG. 12, for example, another embodiment of a device100(shown inFIG. 3) for treating a mitral valve defect is shown. The device includes a frame410that includes an adjustable member420and a fixed member430. The adjustable member420may include two connected ends422,424that are configured to be engaged with corresponding ends432,434of the fixed member430. The adjustable member420in the embodiment ofFIG. 12may include free ends426,428that are arranged opposite each other and thus define an adjustment space440therebetween. The frame410may thus define a conformable shape formed by the fixed member430and the adjustable member420, and a perimeter of the shape may be defined by a line extending nominally along the fixed member430and the adjustable member420and across the adjustment space440from one free end426to the other428. As described in greater detail below, the perimeter of the shape defined by the frame may be adjustable via the adjustability of a distance measured along the adjustable member420from one connected end422to the other connected end424, such as by increasing or decreasing the size of the adjustment space440(e.g., the distance between the free ends426,428). The device may be configured to be positioned proximate a base portion of a mitral valve and the device may be configured to be adjusted to conform to a shape of the mitral valve being treated so as to improve opening or closure of the mitral valve.

Accordingly, in embodiments such as the embodiment shown inFIG. 12, each of the fixed member420and the adjustable member430may define a lumen. The frame410may further comprise a cinching member450that extends through the respective lumens of the fixed member420and the adjustable member430, and the cinching member may be movable with respect to the fixed member and the adjustable member to adjust the perimeter of the shape (e.g., making the nominal diameter of the frame larger or smaller). In this regard, the two free ends426,428of the adjustable member420may be configured to be moved with respect to each other in response to a corresponding movement of the cinching member450. The cinching member450is shown with the surrounding fixed member430and adjustable member420removed for purposes of explanation inFIG. 13.

The cinching member450may comprise one or more wires that are attached to each other (e.g., via soldering or welding) to form a loop that defines the general shape of the frame and, by extension, the device. For example, in the depicted embodiment, two flat wires disposed in the fixed member430(shown inFIG. 12) may be attached (e.g., welded) to a round wire disposed in the adjustable member420(also shown inFIG. 12) and, in some cases, extending at least partially into the fixed member430via the respective lumens.

As depicted inFIG. 13, the cinching member450may comprise two slotted ends452,454that are disposed within the fixed member430(shown inFIG. 12). The slotted ends452,454may be ends of flat wires, as described above, into which slots455are cut (e.g., via laser cutting, etc.). The device may further comprise an adjustment mechanism460that is configured to be actuated by a user to engage the slotted ends452,454of the cinching member450and move the slotted ends with respect to each other to adjust a length of the cinching member, thereby increasing or decreasing the distance between the free ends426,428of the adjustable member420shown inFIG. 12. The adjustment mechanism460is shown in greater detail inFIGS. 14-18. InFIGS. 14 and 15, for example, the adjustment mechanism460is shown engaged with the slotted ends452,454of the cinching member450. InFIG. 16, one of the slotted ends452is removed, and inFIGS. 17, 17A, and 18the adjustment mechanism460is shown in assembled (FIGS. 17 and 17A) and exploded (FIG. 18) configurations apart from the cinching member450, for purposes of explanation.

With reference now toFIGS. 17 and 18, the adjustment mechanism460may comprise a gear462. The gear462may have a first engaging surface464and a second engaging surface466, where the first and second engaging surfaces are positioned approximately perpendicular to each other, as shown. The first engaging surface464may extend about an outer circumference of the gear462and may define radially extending gear teeth465that are configured to mesh with the slots455defined in the slotted ends452,454of the cinching member450, as shown inFIGS. 14-16. In this way, rotation of the gear462via a user's actuation of the adjustment mechanism460, as described in greater detail below, may serve to move the slotted ends452,454either towards or away from each other, depending on the direction of rotation of the gear. In the depicted embodiment, and with reference toFIGS. 14 and 15, rotation of the gear as a result of actuation of the adjustment mechanism460in the counterclockwise direction (represented by the arrow CCW) serves to move the slotted ends452,454towards each other, thereby making the size (e.g., the nominal diameter) of the cinching member450(FIG. 13) and the frame410(FIG. 12) (and therefore the device) smaller. Actuation of the adjustment mechanism460in the opposite direction would similarly make the size of the cinching member450, the frame410, and the device larger by moving the slotted ends452,454away from each other.

In some embodiments, the adjustment mechanism460may comprise a locking member480that allows the gear462to be rotated solely in a first direction (e.g., the counterclockwise direction CCW shown inFIGS. 14 and 15) when the gear is in a first axial position and in a second direction (e.g., the clockwise direction) when the gear is in a second axial position. In this regard, and with reference toFIGS. 17, 17A, and 18, the gear462may be configured to cooperate with a spring470that contacts an ungeared surface468of the gear, such that in a rest position (e.g., when the user is not actuating or contacting the adjustment mechanism), the gear462is in the first axial position, and the spring is uncompressed (or relatively uncompressed, as compared to when the gear is in the second axial position, described below).

The locking member480may be configured to engage the gear462via contact between locking protrusions482defined in the locking member480, which extend toward the second engaging surface466of the gear462, and ramped teeth467defined in the second engaging surface466. In this regard, each ramped tooth467may include a locking surface467aand a sliding surface467b, shown inFIG. 17. When the gear462is in the first axial position, shown inFIG. 17, the locking protrusion482may be configured to engage the locking surface467aof a corresponding ramped tooth467, such that movement of the gear in the clockwise direction (in the depicted embodiment) is prevented.

An actuation end485of the gear462, in which is defined an opening486configured to receive a sizing tool (e.g., an Allen wrench-type of tool, not shown), may be received through an opening483defined in the locking member480. A user may thus actuate the adjustment mechanism460by inserting the sizing tool into the opening486in the actuation end485of the gear462and rotating the gear. In the passively locked configuration shown inFIG. 17, the user will only be able to rotate the gear in the counterclockwise direction (shown inFIGS. 14 and 15). This is because the locking protrusions482of the locking member480are able to slide along the corresponding sliding surfaces467bof the ramped teeth467via rounded ends of the locking protrusions. The gear462may be movable independently of the locking member480, as shown, and the movement of the locking protrusions482along the sliding surfaces may serve to push the gear against the force of the spring470, compressing the spring somewhat as each ramped tooth is cleared. If the user attempts to rotate the gear462in the opposite direction (e.g., clockwise in this example), the gear will not move an appreciable amount due to the engagement of the locking protrusions482with the corresponding locking surfaces467aof the ramped teeth467, as shown inFIG. 17. Thus, in the configuration shown inFIG. 17, the user would only be able to make the size of the cinching member450(FIG. 13) smaller, decreasing the size of the device.

By applying an axial force F1, as depicted inFIG. 17, via the tool received in the opening486, however, the user may push the gear462against the force of the spring470by a great enough distance (while the locking member480is not moved) so that the user may be able to rotate the gear462without causing engagement of the locking protrusions482with the ramped teeth467, as shown inFIG. 17A. In this way, the user may be able to rotate the gear462in either direction and, by rotating the gear in the clockwise direction, may enlarge the size of the device by applying an axial force F1to the adjustment mechanism460prior to rotationally actuating the adjustment mechanism and maintaining the axial force as the gear462is rotated. Once the actuation is complete, the user may remove the tool from the opening486, and the gear462may return to the first axial position in which the actuation mechanism460is passively locked by virtue of the bias imparted by the spring470.

In some embodiments, the device100may further be configured such that, in addition to being adjustable with respect to a circumference of the device, an elevation of the device or portions of the device is also adjustable. In this regard, a portion of the device corresponding to one of the leaflets of the mitral valve (e.g., the posterior leaflet) may be raised or lowered with respect to a nominal plane of the device (e.g., a plane defined by the portion of the device corresponding to the other of the leaflets of the mitral valve, such as the anterior leaflet in this example). In this way, the device100may be adjustable in multiple dimensions to accommodate the type of repair needed to effect an optimum closure of the patient's valve, such as to compensate for a prolapsed leaflet by raising such a leaflet up.

Accordingly, in some cases, with reference toFIGS. 4 and 12, the frame110,410(or at least portions of the frame) may comprise a malleable material. For example, the frame110,410or at least a portion of the frame, such as the adjustable member120,420or portions thereof, may comprise a material that can be bent or shaped when a force is applied to it. Thus, in such embodiments, the surgeon may be able to bend or adjust the shape or elevation of the frame110,410to accommodate the anatomy of the patient's mitral valve and surrounding tissue. The malleable portions may, for example, be provided near the commissures of the device. In other embodiments, the frame110may comprise a flexible material that is configured to flex and move in response to the force applied to the device once it is installed in the heart. Such flexibility may, for example, allow the device to accommodate contractions of the annulus85(FIG. 2) as the heart pumps blood through the different chambers of the heart. In some embodiments, the frame110,410may comprise a metal alloy such as nitinol or stainless steel, or a polymer material.

In other cases, the elevation of the device may be adjusted via hinges provided near the commissures. Referring toFIGS. 6 and 7, for example, the frame110may, in some embodiments, comprise at least one hinge140proximate adjoining ends of the adjustable member120and the fixed member130. In the depicted embodiment, the frame110includes two hinges140formed in a portion of the fixed member130. In this regard, the respective end132,134of the fixed member130may include a first hinge portion360and a second hinge portion365, where the second hinge portion365is configured to receive the end122,124of the adjustable member (e.g., as described above). As illustrated inFIG. 6, the first hinge portion360and the second hinge portion365may be pivotally connected via a pin370. A series of locking pins375may be provided at predefined intervals within the first hinge portion360that are configured to engage a corresponding opening or concavity of the second hinge portion365, such that the second hinge portion is held in place at a certain angle (which may be zero) with respect to the first hinge portion360based on which locking pin375is engaged. As a result, by selecting the appropriate locking pin375, the second hinge portion365may be rotated above the pin370and the first hinge portion360to a desired one of the preset angles.

In other embodiments, such as the embodiment depicted inFIG. 12, the frame410may comprise at least one hinge540proximate adjoining ends432,422,434,424of the adjustable member420and the fixed member430. As noted above with respect to the embodiment ofFIG. 3, the at least one hinge540may be configured to allow adjustment of an elevation of the frame410with respect to a reference plane passing through the fixed member430. With reference toFIGS. 12 and 19, for example, the at least one hinge540may comprise a first hinge portion560connected to an end432of the fixed member430and a second hinge portion565connected to a corresponding connected end422of the adjustable member420. The second hinge portion565may be configured to be unlocked from the first hinge portion560upon receipt of a pinching force applied by a user to the at least one hinge540, thereby allowing adjustment of the elevation of the frame410, as described in greater detail below with reference toFIGS. 20 and 21.

As depicted inFIG. 20, which shows the hinge540apart from the fixed member430and the adjustable member420, the first hinge portion560may comprise a housing570and a pin assembly580, where the pin assembly is movable with respect to the housing570.FIG. 21shows the hinge540with the housing570of the first hinge portion560removed, for purposes of explanation of the operation of the hinge.

With reference toFIG. 21, the pin assembly580may include a main pin582that extends between an actuating portion584and a connecting portion586of the pin assembly. The second hinge portion565may in turn comprise a socket extension520defining a main through hole522and a plurality of locking holes524. The socket extension520may be configured to fit in a receiving slot572defined by the housing570, as shown inFIG. 20. The receiving slot572of the housing570of the first hinge portion560may, in turn, be formed by receiving extensions574,576of the housing570.

The actuating portion584of the pin assembly580may be disposed on an opposite side of the socket extension520and the receiving extensions574,576with respect to the connecting portion586, such that the main pin582slideably extends through the main through hole522of the socket extension520and corresponding receiving holes575,577of the receiving extensions574,576. Furthermore, with reference toFIG. 21, a locking pin588may extend from the connecting portion586towards the socket extension520of the second hinge portion565and may be configured to be received by each of the locking holes524. In the depicted embodiment, for example, four locking holes524are provided, and the locking pin588is received by the first locking hole.

The pin assembly580may be configured to cooperate with a spring590to maintain the first and second hinge portions560,565in a locked state, in which the locking pin588is engaged with one of the locking holes524. In this regard, the spring590may be disposed around the main pin582between a surface of the socket extension520and the actuating portion584, such that, in an unactuated state of the hinge540, the connecting portion586of the pin assembly580is biased toward the socket extension520, and the locking pin588is engaged with one of the locking holes524, as shown inFIG. 21. As such, in the unactuated state shown inFIG. 21, the first hinge portion560and the second hinge portion565(FIG. 20) are not movable with respect to each other, and the position of the fixed member430with respect to the adjustable member420is locked and unchangeable.

To change a position of the first hinge portion560with respect to the second hinge portion565, such as by rotating the first hinge portion560about an axis A of the main pin582, a force F2may be applied to the actuating portion584along the axis A to counteract the biasing force of the spring590and move the pin assembly580along the axis A such that the connecting portion586moves away from the socket extension520and the locking pin588moves out of engagement with the corresponding locking hole524. The pinching force F2may be applied, for example, by a user who places an index finger on the actuation portion584and a thumb on the housing570on an opposite side of the hinge.

With the locking pin588disengaged from the corresponding locking hole524, the first hinge portion560(FIG. 20) may be moved with respect to the second hinge portion so as to adjust an angle of the adjustable member420with respect to the fixed member430, as described above. Once the desired angle is achieved between the adjustable member420and the fixed member430, the force F2may be discontinued, and the locking pin588may, as a result, be moved back toward another corresponding locking hole524to lock the first hinge portion560in place with respect to the second hinge portion565as a result of the force of the spring590.

Accordingly, the positions of the locking holes524may be configured to provide certain predefined angles between the fixed member430and the adjustable member420. In some embodiments, the at least one hinge540shown inFIG. 20may be configured to allow adjustment of the elevation to an angle between approximately 0° (e.g., no elevation) to approximately 20°. In the depicted embodiment ofFIG. 21, for example, each hole588may represent an incremental increase in the elevation angle, such that the first locking hole524(with which the locking pin588is engaged inFIG. 21), represents an elevation of approximately 0°; the next adjacent locking hole represents an elevation of 5°; the next adjacent locking hole represents an elevation of 10°; and the last locking hole represents an elevation of 15°. Although four locking holes524are shown inFIG. 21, other embodiments may have more or fewer locking holes, so as to provide a greater or smaller range of elevation adjustability. For example, three holes may allow an adjustment of the hinge from 0° to 10°, whereas five holes may allow an adjustment of the hinge from 0° to 20°. Moreover, the spacing of the holes may affect the level adjustability. For example several holes spaced relatively close to each other may provider a finer tune adjustment (e.g., providing increments of 2°, 3°, 4°, or 5° between locked positions), whereas several holes spaced relatively far from each other may provider a courser level of adjustment (e.g., providing increments of 5° to 10° between locked positions). Although in the depicted embodiment ofFIGS. 20 and 21incremental increases or decreases in the elevation can be accomplished, in other embodiments the change in elevation may made in a non-incremental fashion (e.g., continuously to any angle within a range of possible angles, such as approximately 0° to 20°).

Turning again toFIGS. 3, 4, and 12, in some embodiments, the frame110,410may comprise a predefined saddle shape. The saddle shape may, for example, be configured to accommodate a corresponding saddle shape of the base portion of the mitral valve to which the device is to be applied. The general configuration of the device (e.g., nominal size and shape) may be based, in some cases, on cardiac ECHO data analysis of different pathologies. As an example, for a device100configured to be installed on the mitral valve, the pathologies considered may be Barlow's disease and ischemic mitral regurgitation. Moreover, in some embodiments, the adjustable member120,420may be configured (e.g., sized and shaped) to be positioned proximate the posterior leaflet63(FIG. 2), whereas the fixed member130,430may be configured to be positioned proximate the anterior leaflet62. In this way, the configuration of the adjustable member120,420(e.g., the overall size of the frame110,410as well as the elevation of the adjustable member with respect to the reference plane passing through the fixed member) may be adequately adjusted and customized to the particular patient's anatomy to provide the appropriate degree of support to the posterior leaflet63, as the posterior leaflet63has been observed in many cases to move and experience prolapse more often the anterior leaflet62.

Turning now toFIG. 3, the device100may further comprise an outer covering150surrounding the frame110,410. The outer covering150may, for example comprise a biocompatible fabric, such as Gore-tex® fabric. In other embodiments, the outer covering150may comprise a polymer extrusion, such as silicone. In still other embodiments, the outer covering150may comprise multiple layers. For example, the frame110,410may be encased by a silicone extrusion, which is further encased by a layer of polymer material (e.g., extended polytetrafluoroethylene (ePFTE)) or polyester. Moreover, the outer covering150may, in some embodiments, be continuous, as illustrated, such that the outer covering150completely surrounds and encloses the frame110,410. In embodiments in which the surgeon requires access to certain portions of the frame110,410, such as via access ports (described below) or adjustment ports, the outer covering150may include one or more dry seals that provide such access to internal portion, yet prevent bodily fluids from entering. Moreover, areas of the outer covering150that include such dry seals or access points may comprise different materials from other portions of the outer covering, such as by including silicone material in the areas of the dry seals or access points.

In some embodiments, the outer covering150may be configured to accommodate the largest possible perimeter of the frame110. For example, the frame110,410may be configured to be adjustable from a maximum perimeter of approximately 33 mm to a minimum perimeter of approximately 25 mm, e.g., via a locking mechanism that prevents expansion or contraction of the size of the device past a certain threshold, as described above. In this case, the outer covering150may be sized to have a maximum perimeter of about 33 mm, such that when the frame is adjusted to a smaller size perimeter, the outer covering may be configured to form one or more accordion-like structures160(shown inFIG. 8). InFIG. 8, the accordion-like structures160are formed proximate the underlying juncture of the adjustable member120with the fixed member130(e.g., with excess material bunching up in portions near the juncture); however, in other embodiments, such as the embodiment ofFIGS. 12-21, the accordion-like structure160may be formed proximate the adjustment space440shown inFIG. 12or near other portions of the frame where adjustments in size may occur.

In addition to allowing a surgeon to effect adjustment of the device100, such as during a procedure in which the device is installed at the patient's mitral valve, in some embodiments, the device100may be configured to allow for real-time adjustments of the device post-operatively in a minimally invasive manner (e.g., without requiring surgery).

Turning toFIG. 10, for example, in some embodiments the ends122,124of the adjustable member120may comprise extensions380,385that extend from the ends, through a respective portion of the fixed member130, and out through an access port390of the fixed member and the outer covering150. The extensions380,385may, in some cases, be separate wires that are connected to or otherwise attached to the ends122,124of the adjustable member120, whereas in other cases the extensions380,385may be integral to each respective end122,124, such as when the ends themselves extend through the fixed member to the access port390. In such cases, the portions of the adjustable member120that form the ends122,124(e.g., proximate the commissures) may have a predefined thickness, such as approximately 2 mm to 4 mm in diameter, and may thin out as they extend through the fixed member130and form the extensions380,385to a diameter of, for example approximately 0.3 mm to 1 mm, such as 0.35 mm.

In some embodiments, the extensions380,385may have a length of approximately 80 cm to 100 cm and may thus be threaded through a patient's vasculature to an access point in the patient's neck, such as using a snare inserted from a location outside the body (through the patient's vasculature) to pull the extensions out from the device via the access point and out of the patient's body. The ends of the extensions380,385may then be buried under the patient's skin such that they are accessible to the surgeon post-operatively from outside the body. In this way, the size of the device100(e.g., the diameter of the device) may be adjusted post-operatively in a minimally invasive manner via the extensions380,385, such as 3 months to 6 months following placement of the device on the mitral valve. This may be necessary, for example, due to changes in the anatomy of the patient's heart, such as remodeling of the ventricle as the heart heals or worsens after installation of the device.

For example, following a procedure in which the device100is installed, and after the patient is taken off the heart-lung machine, the function of the patient's heart may be analyzed using echocardiography. If it is determined that the device100requires adjustment (e.g., needs to be made smaller) to compensate for changes to the heart so as to improve the closure of the mitral valve, the extensions380,385may be accessed from underneath the patient's skin and a catheter may be inserted into the patient's vasculature over the extensions to the location of the access port390. The surgeon may then pull on one or both extensions380,385, which are in turn connected to the ends122,124of the adjustable member120, to cinch the diameter of the device (e.g., make the device diameter smaller).

In this regard, the extensions380,385may be configured to move in one direction with respect to the access port390, such as to only be pulled out of the access port to make the diameter of the device smaller. For example, a surface of the extensions380,385in a portion proximate the access port390may comprise burs392or other angled protrusions that, although tapered or angled to allow withdrawal from the access portion, resist reentry into the fixed member130, as shown inFIG. 10A. Once the device has been cinched to the appropriate diameter, the extensions380,385may be secured with respect to the fixed member130(such as via burs392, by twisting the extensions together, or via a separate locking mechanism on the access port390), separated from the adjustable member120(e.g., by applying a force to a predefined area of weakness of the extensions380in a region proximate the access port to break off an excess length of the extensions), and removed from the body. In some embodiments, radiopaque markers may be provided on portions of the device100(e.g., on parts of the adjustable member, the fixed member, the extensions, etc.) to allow the surgeon to see the position of the device as installed on the mitral valve for making such real-time, remote adjustments. Although features for allowing for real-time adjustments as described above are described in terms of the embodiment ofFIG. 4, in some cases one or more of the described features may be incorporated into other embodiments, such as the embodiment ofFIG. 12in a similar fashion.

Turning now toFIG. 11, in some embodiments, a method is provided for treating a mitral valve defect. A device may be provided having a frame comprising an adjustable member and a fixed member, wherein each end of the adjustable member is engaged with a corresponding end of the fixed member to form a closed shape.FIG. 11, Block200. As described above in detail, at least one end of the adjustable member may be configured to be adjustably received by the corresponding end of the fixed member, such that a perimeter of the closed shape defined by the frame is adjustable. The device may be placed proximate a base portion of the mitral valve to be treated.FIG. 11, Block210. This may be done via a full or mini-thoracotomy or, in some cases, less invasive surgical procedures may be used.

A perimeter of the closed shape defined by the frame may be adjusted by moving the adjustable member with respect to the fixed member. Block220. For example, the surgeon may move one or both ends of the adjustable member farther into the corresponding ends of the fixed member to decrease the perimeter of the closed shape (e.g., decrease the overall size of the device). Conversely, the surgeon may withdraw one or both ends of the adjustable member from the corresponding ends of the fixed member to increase the perimeter of the closed shape (e.g., increase the overall size of the device). As described above, adjustment of the perimeter of the closed shape defined by the frame may allow the device to fit the mitral valve being treated so as to improve opening or closure of the mitral valve.

In some embodiments, the frame may comprise at least one hinge proximate adjoining ends of the adjustable member and the fixed member. In such embodiments, the method may further include adjusting an elevation of the frame with respect to a reference plane passing through the fixed end by moving portions of the frame with respect to each other, as described above. In other embodiments, the frame may comprise a malleable material, and the method may further comprise adjusting an elevation of the frame with respect to a reference plane passing through the fixed member by applying pressure to portions of the frame, as noted above.

In other embodiments, as shown inFIG. 22, a method for treating a mitral valve defect is provided that comprises providing a device having a frame comprising an adjustable member and a fixed member (such as a frame configured similarly to the frame410ofFIG. 12), wherein each connected end of the adjustable member is engaged with a corresponding end of the fixed member, and wherein a distance measured along the adjustable member from one connected end to the other connected end is configured to be adjustable, such that a perimeter of a shape defined by the frame is adjustable, illustrated in block600. The device may be placed proximate a base portion of the mitral valve to be treated, as shown in block610, and the device may be adjusted by adjusting the perimeter of the shape defined by the frame so as to allow the device to conform to a shape of the mitral valve being treated for improving opening or closure of the mitral valve, as shown in block620.

In some cases, adjusting the size of the device may include actuating an adjustment mechanism of the frame, where the adjustment mechanism is configured to engage slotted ends of a cinching member extending through the fixed member and the adjustable member. Actuation of the adjustment mechanism may, in turn, move the cinching member with respect to the fixed member and the adjustable member. Adjusting the size of the device may further include enlarging the size of the device by applying an axial force to the adjustment mechanism while actuating the adjustment mechanism, as described above.

The frame may, in some embodiments, comprise at least one hinge proximate adjoining ends of the adjustable member and the fixed member. In such cases, an elevation of the frame may be adjusted with respect to a reference plane passing through the fixed member by actuating the at least one hinge, as shown in block630. Actuating the at least one hinge may include applying a pinching force to the at least one hinge, and the hinge(s) may be configured to allow adjustment of the elevation to an angle between approximately 0° to approximately 20°. In other embodiments, including embodiments that do not incorporate hinges as described above, the frame may comprise a malleable material, and the method may further include adjusting an elevation of the frame with respect to a reference plane passing through the fixed member by applying pressure to portions of the frame.

The devices and methods depicted in the figures and described above represent only certain configurations of the device and method for treating a mitral valve. The particular configurations and methods will depend on the patient's anatomy, the condition and location of the target site, the preferences of the practitioner, and other considerations. Moreover, certain features described with respect to one depicted embodiment may be interchanged with or combined with other features described with respect to another depicted embodiments in some cases. For example, a mechanism for adjusting the size of the device (e.g., enlarging or decreasing the perimeter of the frame) described with respect to one embodiment may be combined with a mechanism for adjusting the elevation described with respect to another embodiment, etc. In some cases, one or both of the adjustable member and the fixed member of the frame may be comprised of multiple pieces that are connected to each other and/or portions of the other member. Furthermore, the fixed member in some embodiments may be configured to allow for a certain amount of flexibility, such that adjustments in the size of the adjustable member as described above according to various embodiments may be accommodated, and a more comfortable fit with the mitral valve may be provided.

Accordingly, embodiments of the device described herein and illustrated in the figures provide mechanisms for treating a mitral valve defect by fitting the device to the actual pathology of the valve, rather than attempting to replicate a healthy valve (which the patient does not have). In so doing, the device allows the patient's actual valve to work as well as possible, given the valve's diseased condition.

The actual pathology of the valve is accommodated by providing for multiple dimensions of adjustability of the device, including adjustability of the size (e.g., diameter) of the device as well as adjustability of the elevation or inclination of one portion of the device (e.g., the portion supporting the posterior leaflet) with respect to another portion of the device. By lifting up one of the leaflets to more efficiently coapt with the other leaflet, the need to modify chordae may be reduced or eliminated. In other words, adjustments may be made at the level of the valve. Moreover, embodiments of the device allow for real-time adjustments to be made, such that the surgeon is not limited to fitting the device to the patient's valve at the time of the procedure installing the device, but can also monitor the functioning of the device and any changes to the anatomy of the heart after the device is installed and can make adjustments post-operatively in a minimally invasive manner to ensure the best fit of the device to the valve and the best operation of the patient's existing valve structure.