Patent Description:
Valvular heart disease, and specifically aortic and mitral valve disease, is a significant health issue in the United States. Valve replacement is one option for treating heart valves diseases. Traditional valve replacement surgery, the orthotopic replacement of a heart valve, is an "open heart" surgical procedure. Briefly, the procedure necessitates a surgical opening of the thorax, initiation of extra-corporeal circulation with a heart-lung machine, stopping and opening the heart, excision and replacement of the diseased valve, and re-starting of the heart. While valve replacement surgery typically carries a <NUM>-<NUM>% mortality risk in otherwise healthy persons, a significantly higher morbidity is associated with the procedure, largely due to the necessity for extra-corporeal circulation. Further, open heart surgery is often poorly tolerated in elderly patients. Thus, if the extra-corporeal component of the procedure could be eliminated, morbidities and cost of valve replacement therapies would be significantly reduced.

While replacement of the aortic valve in a transcatheter manner is the subject of intense investigation, lesser attention has been focused on the mitral valve. This is in part reflective of the greater level of complexity associated with the native mitral valve and thus a greater level of difficulty with regard to inserting and anchoring the replacement prosthesis.

Recent developments in the field have provided devices and methods for mitral valve replacement with reduced invasion and risk to the patient. Such devices may include a prosthetic valve disposed within the native valve annulus and held in place with an anchor seated against an exterior surface of the heart near the ventricular apex, and such anchors must be at least a certain size to seat against the heart with adequate security. Methods of implanting such devices therefore typically require providing an intercostal puncture of significant size to accommodate the anchor. Trauma to the patient increases as a function of the diameter of the puncture. Accordingly, methods and devices for anchoring a prosthetic heart valve that avoid the need for an intercostal puncture would improve patient outcomes.

<CIT> describes a prosthetic heart valve for treatment of a diseased native heart valve, the prosthetic heart valve having a crescent shaped stent, at least one leaflet mounted to the stent, and an anchor, wherein the anchor is connected to the stent by means of at least one tether. The anchor may comprise a locking structure being configured to allow passage of a portion of an upper flared portion of the stent down to the tether portion towards the left ventricle, and to resist the subsequent movement in the opposite direction. The anchor may have a coil-shaped distal portion for engaging muscular tissue of the heart.

According to the invention according to claim <NUM>, a prosthetic heart valve system includes a prosthetic heart valve, an anchor and a tether.

According to another embodiment of the disclosure, a prosthetic heart valve system includes a prosthetic heart valve, an anchor and a tether. The prosthetic heart valve may have an expandable stent and a prosthetic valve assembly disposed within the stent. The prosthetic valve assembly may be configured to allow blood to flow in a direction from an inflow end of the stent toward an outflow end of the stent and to substantially block blood from flowing from the outflow end of the stent toward the inflow end of the stent. The prosthetic heart valve may include a tether connecting portion. The anchor may be adapted to be disposed on or adjacent an epicardial surface of a heart of a patient. The tether may have a distal end coupled to the anchor and extend proximally from the anchor. The tether connecting portion may include a stem having a radially expanded condition, a radially collapsed condition, and a barb extending radially inward from the stem. The barb may be configured to pierce the tether upon transition of the stem from the radially expanded condition to the radially collapsed condition.

According to another embodiment of the disclosure, a prosthetic heart valve system includes a prosthetic heart valve, an anchor, a tether clip and a tether. The prosthetic heart valve may have an expandable stent and a prosthetic valve assembly disposed within the stent. The prosthetic valve assembly may be configured to allow blood to flow in a direction from an inflow end of the stent toward an outflow end of the stent and to substantially block blood from flowing from the outflow end of the stent toward the inflow end of the stent. The prosthetic heart valve may include a tether connecting portion. The anchor may be adapted to be disposed on or adjacent an epicardial surface of a heart of a patient. The tether may have a distal end coupled to the tether clip, a proximal end coupled to the tether connecting portion, a first intermediate tether portion looped around the anchor, and a second intermediate tether portion. The second intermediate tether portion may be threaded through an aperture in the tether clip, and the tether clip may be configured to slide along the second intermediate tether portion to adjust a tension of the tether.

According to another embodiment of the disclosure, a method of implanting a prosthetic heart valve includes positioning an anchor adjacent a ventricular wall while a tether is coupled to and extends proximally from the anchor. The prosthetic heart valve may be advanced distally along the tether while the anchor is positioned adjacent the ventricular wall. The prosthetic heart valve may be deployed into a native valve annulus. The tether may be pulled in a proximal direction to tension the tether. The prosthetic heart valve may be fixed to the tether while the tether is tensioned.

As used herein, the term "proximal," when used in connection with a delivery device or components of a delivery device, refers to the end of the device closer to the user of the device when the device is being used as intended. On the other hand, the term "distal," when used in connection with a delivery device or components of a delivery device, refers to the end of the device farther away from the user when the device is being used as intended. Further, the term "inflow end" when used herein in connection with a prosthetic atrioventricular valve refers to the end of the prosthetic valve nearest the atrium when the prosthetic valve is implanted in an intended position and orientation, while the term "outflow end" refers to the end of the prosthetic valve nearest the ventricle when the prosthetic valve is implanted in the intended position and orientation. As used herein, the terms "substantially," "generally," "approximately," and "about" are intended to mean that slight deviations from absolute are included within the scope of the term so modified.

An exemplary prosthetic heart valve <NUM> as may be used with various embodiments of the present disclosure is shown in an exploded view in <FIG>. Valve <NUM> includes an inner structure or assembly <NUM> and an outer structure or assembly <NUM>. Valve <NUM> is coupled to a tether <NUM> and a collapsible tether anchor <NUM>.

Inner assembly <NUM> may include an inner frame <NUM>, outer wrap <NUM> which may be cylindrical, and leaflet structure <NUM> (including articulating leaflets <NUM> that define a valve function). Leaflet structure <NUM> may be sewn to inner frame <NUM>, and may use parts of inner frame <NUM> for this purpose, although methods of attachment other than sutures may be suitable. Inner assembly <NUM> is disposed and secured within outer assembly <NUM>, as described in more detail below.

Outer assembly <NUM> includes outer frame <NUM>. Outer frame <NUM> may also have in various embodiments an outer frame cover of tissue or fabric (not pictured), or may be left without an outer cover to provide exposed wireframe to facilitate in-growth of tissue. Outer frame <NUM> may also have an articulating collar or cuff (not pictured) covered by a cover <NUM> of tissue or fabric.

Tether <NUM> is connected to valve <NUM> by inner frame <NUM>. Thus, inner frame <NUM> includes tether connecting or clamping portion <NUM> by which inner frame <NUM>, and by extension valve <NUM>, is coupled to tether <NUM>.

Inner frame <NUM> is shown in more detail in <FIG>. Inner frame <NUM> can be formed from a milled or laser-cut tube of a shape-memory material such as, for example, nitinol. Inner frame <NUM> is illustrated in <FIG> in an initial state, e.g., as milled or laser-cut, but cut longitudinally and unrolled into a flat sheet for ease of illustration. This initial state may generally correspond to a collapsed condition. Inner frame <NUM> is shown unconstrained, e.g., to the expanded, deployed configuration, in the side view and bottom view of <FIG>, respectively. Inner frame <NUM> can be divided into four portions corresponding to functionally different portions of inner frame <NUM> in final form: apex portion <NUM>, body portion <NUM>, strut portion <NUM>, and tether connecting portion <NUM>. Strut portion <NUM> includes six struts, such as strut 143A, which connect body portion <NUM> to connecting portion <NUM>. A greater or fewer number of struts 143A is contemplated herein.

Connecting portion <NUM> includes longitudinal extensions of the struts 143A, connected circumferentially to one another by pairs of v-shaped connecting members, which may be referred to herein as "micro-V's. " Connecting portion <NUM> is configured to be radially collapsed by application of a compressive force, which causes the micro-V's to become more deeply V-shaped, with each pair of vertices moving closer together longitudinally and the open ends of the V shapes moving closer together circumferentially. When collapsed, connecting portion <NUM> can clamp or grip one end of tether <NUM>, either connecting directly onto a tether line (e.g., braided filament line) or onto an intermediate structure, such as a polymer or metal piece that is, in turn, firmly fixed to the tether line. The foregoing is merely exemplary and other techniques can be used to connect tether <NUM> to connecting portion <NUM>, as will be discussed below in further detail.

In contrast to connecting portion <NUM>, apex portion <NUM> and body portion <NUM> are configured to be expanded radially. Strut portion <NUM> forms a longitudinal connection, and radial transition, between the expanded body portion <NUM> and the compressed connecting portion <NUM>.

Body portion <NUM> includes six longitudinal posts, such as post 142A, although the body portion may include a greater or fewer number of such posts. The posts 142A can be used to attach leaflet structure <NUM> to inner frame <NUM>, and/or can be used to attach inner assembly <NUM> to outer assembly <NUM>, such as by connecting inner frame <NUM> to outer frame <NUM>. In the illustrated example, posts 142A include apertures 142B through which connecting members (such as suture filaments and/or wires) can be passed to couple the posts to other structures.

Outer frame <NUM> of valve <NUM> is shown in more detail in <FIG>. Outer frame <NUM> can be formed from a milled or laser-cut tube of a shape-memory material such as, for example, nitinol. Outer frame <NUM> is illustrated in <FIG> in an initial state, e.g., as milled or laser-cut, but cut longitudinally and unrolled into a flat sheet for ease of illustration. This initial state may generally correspond to the collapsed condition. Outer frame <NUM> can be divided into a coupling portion <NUM>, a body portion <NUM>, and a flared portion <NUM>, as shown in <FIG>. Coupling portion <NUM> may include multiple openings or apertures 171A by which outer frame <NUM> can be coupled to inner frame <NUM>, as described in greater detail below.

Flared portion <NUM> may include an indicator <NUM>. In one example, indicator <NUM> is simply a broader portion of the wire frame element of flared portion <NUM>. Indicator <NUM> may be more apparent in radiographic or other imaging modalities than the surrounding wireframe elements of flared portion <NUM>. In other examples, indicator <NUM> can be any distinguishable feature (e.g., protrusion, notch, etc.) and/or indicia (e.g., lines, markings, tic marks, etc.) that enhance the visibility of the part of flared portion <NUM> on which it is formed, or to which it is attached. Indicator <NUM> can facilitate the implantation of the prosthetic valve by providing a reference point or landmark that the operator can use to orient and/or position the valve (or any portion of the valve) with respect to the native valve annulus or other heart structure. For example, during implantation, an operator can identify (e.g., using echocardiography) indicator <NUM> when the valve <NUM> is situated in a patient's heart. The operator can therefore determine the location and/or orientation of the valve and make adjustments accordingly.

Outer frame <NUM> is shown in an expanded, deployed configuration, in the side view and top view of <FIG>, respectively. As best seen in <FIG>, the lower end of coupling portion <NUM> may form a roughly circular opening (identified by "O" in <FIG>). The diameter of this opening preferably corresponds approximately to the diameter of body portion <NUM> of inner frame <NUM>, when the inner frame is in the expanded condition, to facilitate the coupling together of these two components of valve <NUM>.

Outer frame <NUM> and inner frame <NUM> are shown coupled together in <FIG> in front, side, and top views, respectively. The two frames collectively form a structural support for a valve leaflet structure, such as leaflet structure <NUM> in <FIG>. The frames support leaflet structure <NUM> in the desired relationship to the native valve annulus, support the coverings for the two frames to provide a barrier to blood leakage between the atrium and ventricle, and couple to the tether <NUM> (by the inner frame <NUM>) to aid in holding the prosthetic valve in place in the native valve annulus by the connection of the free end of the tether and tether anchor <NUM> to the ventricle wall, as described more fully below. The two frames are connected at six coupling points (representative points are identified as "C"). In this embodiment, the coupling of the frames is implemented with a mechanical fastener, such as a short length of wire, passed through an aperture 171A in coupling portion <NUM> of outer frame <NUM> and a corresponding aperture 142B in a longitudinal post 142A in body portion <NUM> of inner frame <NUM>. Inner frame <NUM> is thus disposed within the outer frame <NUM> and securely coupled to it.

An exemplary anchor <NUM> for a prosthetic mitral heart valve is illustrated in <FIG> and <FIG>. Anchor <NUM> includes a first disc <NUM> and a second disc <NUM>, both provided by a wire mesh and centered on an axis X. First disc <NUM> is offset from second disc <NUM> in a first direction along axis X. First disc <NUM> and second disc <NUM> are each biased toward a dome-shaped resting configuration that is concave toward a second direction along axis X, the second direction being opposite the first direction. The resting configuration of first disc <NUM> extends far enough in the second direction along axis X to partially overlap second disc <NUM>.

It should be understood that the illustrated dome shapes are merely exemplary, and first disc <NUM> and second disc <NUM> may be biased differently. For example, either or both of first disc <NUM> and second disc <NUM> may be biased toward a resting configuration that is convex toward the second direction or generally planar. Further, the first disc <NUM> and second disc <NUM> may be biased to different resting configurations. In one example, the first disc <NUM> may be biased toward a dome-shaped resting configuration that is concave toward the second direction while the second disc <NUM> is biased toward a generally planar configuration having about the same diameter location as the widest part of the dome-shaped resting configuration of the first disc <NUM>, as shown in <FIG>. In the arrangement shown in <FIG>, second disc <NUM> is generally planar in shape with a shallow concavity toward the first direction near the center of second disc <NUM>.

Anchor <NUM> may also include a cuff <NUM> for gripping a tether <NUM>, which may be connected to a prosthetic heart valve. Cuff <NUM> is offset from second disc <NUM> in the second direction along axis X. One-way gripping features, such as angled teeth, within cuff <NUM> may permit anchor <NUM> to slide along tether <NUM> in the second direction, but not the first direction. In other embodiments, cuff <NUM> may be fixedly attached to tether <NUM> so that the anchor <NUM> may not slide along the tether.

Anchor <NUM> is flexible, as illustrated in <FIG>, which shows anchor <NUM> with the first disc <NUM> everted from its resting configuration. First disc <NUM> is connected to second disc <NUM> by a neck <NUM> extending between first disc <NUM> and second disc <NUM>. In the illustrated example, neck <NUM> is centered on axis X, but in other examples neck <NUM> may be radially offset from axis X. First disc <NUM>, second disc <NUM>, and neck <NUM> may all be constructed from a single continuous piece or tube of wire mesh. The wire mesh may be formed from a plurality of strands or wires braided into various three-dimensional shapes and/or geometries to engage tissues, or from one or more sheets cut to provide mesh, such as by laser. In one example, the wires form a braided metal fabric that is resilient, collapsible and capable of heat treatment to substantially set a desired shape. One class of materials which meets these qualifications is shape-memory alloys, such as nitinol. The wires may comprise various materials other than nitinol that have elastic and/or memory properties, such as spring stainless steel, tradenamed alloys such as Elgiloy® and Hastelloy®, CoCrNi alloys (e.g., tradename Phynox), MP35N®, CoCrMo alloys, or a mixture of metal and polymer fibers. Depending on the individual material selected, the strand diameter, number of strands, and pitch may be altered to achieve the desired shape and properties of anchor <NUM>. Shape memory materials such as nitinol may be particularly suitable for anchor <NUM> in that shape memory material construction enables anchor <NUM> to consistently return to an intended shape after being compressed and deployed. In other arrangements, anchor <NUM> may be covered by or may incorporate other flexible biocompatible material, such as a fabric. Although anchor <NUM> is one example of an expandable anchor that may be suitable for use with the prosthetic valves of the present disclosure, it should be understood that other anchors, including other expandable anchors, may also be suitable.

<FIG> shows a trans-jugular insertion of an at least partially flexible delivery tube <NUM> for anchor <NUM> and valve <NUM>. Delivery tube <NUM> may be formed of any known material for building catheters, including biocompatible metals such as steel, and may be part of a steerable or flexible catheter system. Delivery tube <NUM> may include an inflexible portion near its distal end to facilitate the intended puncture of tissue and guidance of valve <NUM>. Delivery tube <NUM> is inserted through the patient's jugular vein (not shown), then through superior vena cava <NUM>, right atrium <NUM>, atrial septum <NUM>, left atrium <NUM>, native mitral valve <NUM>, and into left ventricle <NUM>. Tube <NUM> exits left ventricle <NUM> through ventricular wall <NUM> at or near the apex <NUM> of heart <NUM>. A retractable puncturing device (not shown) and a retractable atraumatic tip (not shown) may extend from the distal open end <NUM> of tube <NUM> in alternate stages of insertion of tube <NUM>. The puncturing device may produce openings through atrial septum <NUM> and ventricular wall <NUM> while the atraumatic tip may act to prevent injury to other tissue. Once delivery tube <NUM> has been fully inserted, the distal open end <NUM> of tube <NUM> is positioned outside of ventricular wall <NUM>. The trans-jugular insertion of tube <NUM> may be accomplished by any of variety of methods, such as, for example, guiding tube <NUM> along a guide wire, such as a shape-memory guide wire, inserted through the jugular vein. The flexible nature of anchor <NUM> allows trans-jugular delivery of anchor <NUM> through tube <NUM>. Because tube <NUM>, anchor <NUM>, and valve <NUM> all reach heart <NUM> from the jugular vein, valve <NUM> and anchor <NUM> may be delivered and implanted without any intercostal puncture.

<FIG> shows a trans-femoral insertion of tube <NUM>. Tube <NUM> enters heart <NUM> through inferior vena cava <NUM>, travels through right atrium <NUM>, and punctures septum <NUM> to enter left atrium <NUM>. Tube <NUM> is advanced from left atrium <NUM> through native mitral valve <NUM>, left ventricle <NUM>, and ventricular wall <NUM> such that the open end <NUM> of the tube is positioned outside of wall <NUM> at or near apex <NUM>. As with trans-jugular insertion, guidance of tube <NUM> during trans-femoral insertion may be accomplished using a variety of methods, including guidance along a guide wire.

The trans-jugular and trans-femoral insertions described above are merely exemplary. It should be understood that tube <NUM> could be guided toward heart <NUM> using any suitable method known in the art.

<FIG> illustrate anchor <NUM> in progressive stages of deployment from the open end <NUM> of tube <NUM>. Tube <NUM> is shown in a distalmost position in <FIG>, with open end <NUM> positioned outside of heart <NUM>. Tube <NUM> may be retracted while anchor <NUM> is forced to remain in place, such as by a reversal of a typical Bowden cable arrangement. For example, a semi-rigid cable or wire <NUM> may be inserted through tube <NUM> to contact the proximal end of anchor <NUM>, as shown in <FIG>. Pulling tube <NUM> proximally relative to wire <NUM> causes anchor <NUM> to deploy out from the open end <NUM> of tube <NUM>, as shown in 21B. As shown in <FIG>, retracting tube <NUM> while preventing anchor <NUM> from retreating with the tube into heart <NUM> causes first disc <NUM> of anchor <NUM> to deploy out from the open end <NUM> of tube <NUM> and expand radially relative to axis X. Upon further retraction of tube <NUM>, the bias of first disc <NUM> causes it to curve back onto the outer apex <NUM> of heart <NUM>, as shown in <FIG>. Further retraction of tube <NUM> in <FIG> allows second disc <NUM> to deploy and expand radially relative to axis X within left ventricle <NUM> until second disc <NUM> opens to press against an inner side of wall <NUM>, as shown in <FIG>. Pressure against wall <NUM> results from the elastic bias of first disc <NUM> and second disc <NUM> toward certain resting positions as described above with regard to <FIG>, <FIG>, and <FIG>. First disc <NUM> and second disc <NUM> pressing on opposite sides of wall <NUM> causes anchor <NUM> to grip wall <NUM>. Such progressive expansion from within a narrow tube results in anchor <NUM> adequately securing valve <NUM> to ventricular wall <NUM> without requiring an intercostal puncture through the patient's chest.

In the trans-jugular and trans-femoral delivery routes described above, one end of the tether <NUM> is preferably fixed to the anchor <NUM> before deployment of the anchor <NUM>, including prior to loading the valve <NUM> into tube <NUM>. Tether <NUM> and anchor <NUM> remain attached while anchor <NUM> is delivered to the exterior of ventricular wall <NUM> from within tube <NUM>, and tether <NUM> is uncovered by the retraction of tube <NUM>. In alternate embodiments, the anchor <NUM> and tether <NUM> may be fixed to one another during or immediately after deployment of the anchor <NUM>. The tether <NUM> may extend proximally to a second free end, and the prosthetic valve <NUM> is preferably delivered over the tether <NUM>, using the tether <NUM> as a rail and/or guide, with the tether <NUM> extending through a center portion of prosthetic valve <NUM> while the valve <NUM> is being delivered to the native valve annulus. Once the prosthetic valve <NUM> is at or adjacent the final position within the native valve annulus, the prosthetic valve <NUM> is preferably fixed to the tether <NUM> by engagement or activation of the tether connecting portion <NUM> with the tether <NUM>. This engagement may be accomplished via one or more mechanisms, including those described below, and the engagement may occur just before, during, or just after deployment of the prosthetic valve <NUM>. Much of the below disclosure relates to a further embodiment of tether connecting portion <NUM> to facilitate such a connection between the prosthetic valve <NUM> and the second end of the tether <NUM>. Placement of valve <NUM> into native mitral valve <NUM> may involve affixing tether <NUM> to anchor <NUM> at one end of tether <NUM>, as noted above. It may also involve affixing tether <NUM> to a tensioning mechanism (not shown) at the other end of tether <NUM>. The tensioning mechanism may include a load sensor for measuring tension and will remain outside the body of the patient while anchor <NUM> is inserted through one of the above-mentioned methods. Although it should be understood that the tensioning mechanism may be affixed to the tether after the anchor <NUM> is deployed. Thus, after anchor <NUM> is secured against outer apex <NUM> of heart <NUM>, tether <NUM> may extend from anchor <NUM> to the tensioning mechanism, e.g., the entire length of the path used to insert anchor <NUM> against outer apex <NUM>. One example using an above-mentioned method may embody tether <NUM> extending from anchor <NUM> through ventricular wall <NUM>, left ventricle <NUM>, native mitral valve <NUM>, left atrium <NUM>, atrial septum <NUM>, right atrium <NUM>, superior vena cava <NUM>, exiting the patient through a jugular vein (not shown) and attaching to the tensioning mechanism outside the patient. Maintenance of tether <NUM> in this position may permit valve <NUM> to attach to tether <NUM> outside the patient's body, using tether <NUM> as a guide to follow the path of tether <NUM> to place valve <NUM> within native mitral valve <NUM>. Several embodiments of how valve <NUM> may be secured into place in native mitral valve <NUM> will be explained below in further detail. It should be understood that, if the prosthetic valve <NUM> is fixed to the tether <NUM> after the anchor <NUM> is deployed and the prosthetic valve <NUM> is at or near its final desired position, it may be preferable to fix the prosthetic valve <NUM> to the tether <NUM> by activating or engaging the tether connecting portion <NUM> to the tether <NUM> after the tether <NUM> has been tensioned a desired amount, at which point the coupling of the tether connecting portion <NUM> of the prosthetic valve <NUM> to the tether <NUM> will maintain the desired tension in the tether <NUM>. Such tension may provide certain benefits, for example helping to prevent the prosthetic valve <NUM> from migrating into the atrium. The force on the ventricle from the tension of the tether <NUM> may also facilitate more efficient functioning of the ventricle. Various mechanisms for fixing the prosthetic valve <NUM> to the tether <NUM> after the tether <NUM> has been tensioned are described in greater detail below.

<FIG> show an embodiment of a tether connecting mechanism <NUM> for coupling a prosthetic heart valve similar to valve <NUM> to a tether <NUM> similar to tether <NUM>. In the illustrated embodiment, tether connecting mechanism <NUM> takes the form of a ball and flap mechanism <NUM>. The ball and flap mechanism <NUM> may function to secure valve <NUM> in native mitral valve <NUM> with desired tension on tether <NUM>. Ball and flap mechanism <NUM> may be attached to strut portion <NUM> of valve <NUM> on the end of valve <NUM> nearest anchor <NUM>, i.e. the outflow end, as shown in <FIG>. In other words, the ball and flap mechanism <NUM> may either replace the tether connecting portion <NUM> of inner frame <NUM>, or may be positioned within the tether connecting portion <NUM> of inner frame <NUM>. Tether <NUM> may be substantially similar or identical to tether <NUM>, with at least one exception. For example, at least a portion of tether <NUM> may include balls <NUM>, or other protrusions or enlarged-width structures, spaced from one another along the length of tether <NUM>. In one embodiment, the balls <NUM> are only positioned along the portion of tether <NUM> that is expected to engage the ball and flap mechanism <NUM>. As is described in greater detail below, the balls <NUM> facilitate connection between the tether <NUM> and the prosthetic valve <NUM>, as well as facilitating the maintenance of a desired tension on the tether <NUM>. Tether <NUM> is not limited to the use of balls <NUM>; other examples may include knots, beads, other clamp-on pieces, etc. Ball and flap mechanism <NUM> may include a flap <NUM> hingedly coupled to valve stem body <NUM>, for example by hinge <NUM>. Flap <NUM> may be in a closed position when flap <NUM> sits generally perpendicular to a central longitudinal axis of valve stem body <NUM>, as shown in <FIG>. Flap <NUM> may be in an open position when flap <NUM> sits generally parallel to the longitudinal axis of valve stem body <NUM> as shown in <FIG>. In some embodiments, flap <NUM> may be biased into a closed position by a biasing member, for example a torsion spring (not shown). In the illustrated embodiment, flap <NUM> has a free end generally opposite the end where hinge <NUM> couples the flap <NUM> to the valve stem body <NUM>. The free end of the flap <NUM> may have a generally circular circumference that is interrupted by a substantially "U"-shaped recessed portion, with two free arms of the flap defining portions of the "U"-shaped recess. The recessed portion may be adapted to receive a portion of tether <NUM> therethrough, as shown in <FIG>. The "U"-shaped recessed portion may have a width defined between inner edges of the two free arms, the width of the recessed portion being greater than a diameter of the tether <NUM>, but smaller than a diameter of the balls <NUM>.

As noted above, after the anchor <NUM> has been deployed, the prosthetic valve <NUM> may be guided over the tether <NUM> toward the mitral valve <NUM>, for example, while collapsed in a sheath of a delivery device, with the delivery device sheath and the prosthetic valve <NUM> being fed over the tether <NUM>. During this delivery, the tether <NUM> may be held taut, for example manually or via a tensioning mechanism coupled to the tether <NUM>. During delivery, the valve stem body <NUM> may be the leading end of the prosthetic valve <NUM>. As the valve stem body <NUM> approaches and slides over the balls <NUM> of the tether <NUM>, the first encountered ball <NUM> may cause the flap <NUM> to open. If the flap <NUM> is biased toward the closed condition, it will begin to close as soon as the recessed portion of the flap <NUM> clears the ball <NUM>. The flap <NUM> may be biased toward the closed condition by a torsion spring. Alternatively, the flap <NUM> may be coupled to the tether <NUM> such that the tension in the tether <NUM> may bias the flap <NUM> toward the closed condition. As the prosthetic valve <NUM> continues to approach the native mitral valve <NUM>, the flap <NUM> may continue opening and closing as it passes successive balls <NUM> on the tether <NUM>. The prosthetic valve <NUM> is advanced until it reaches the desired position within the native mitral valve <NUM>. It should be understood that, depending on the position of the balls <NUM> on tether <NUM>, the prosthetic valve <NUM> may reach the desired position in the native mitral valve <NUM> without encountering any of the balls <NUM>. Maintaining a level of tension on the tether <NUM> while the prosthetic valve <NUM> is being advanced distally over the tether <NUM> may help ensure that the flap <NUM> does not cause the tether <NUM> to be pushed distally, but rather the balls <NUM> of the tether <NUM> cause the flap to open upon contact between the flap <NUM> and ball <NUM>.

After prosthetic valve <NUM> has reached the desired position in native mitral valve <NUM>, the prosthetic valve may be ejected from the delivery device and expand (for example via self-expansion or balloon expansion) into the annulus of the native mitral valve <NUM>. Once the position and/or orientation of the prosthetic valve <NUM> is confirmed as desired, the tether <NUM> may be tensioned. Tensioning the tether <NUM> may include pulling the tether <NUM> proximally, for example manually or via a tensioning tool coupled to the free end of the tether <NUM>. In some embodiments, the tensioning tool may grip a portion of the tether <NUM>, with a portion of the tensioning tool being rotated or otherwise activated to pull the tether <NUM>, preferably with a measurement of the tension being measured during the process, for example via a load cell. As the tether <NUM> is tensioned, the pulling/tensioning force causes tether <NUM> and associated balls <NUM> to translate proximally relative to the valve stem body <NUM> of prosthetic valve <NUM> while the prosthetic valve <NUM> is held in place in native mitral valve <NUM>. As each ball <NUM> passes proximally through valve stem body <NUM>, and the relatively large diameter of the ball <NUM> is unable to pass through the recessed portion of flap <NUM>, resulting in the flap <NUM> moving into the open position, with hinge <NUM> facilitating flap <NUM> moving into the open position. While the flap <NUM> is in the open position, the ball <NUM> is permitted to pass proximally through ball and flap mechanism <NUM> as demonstrated in <FIG>. After a ball <NUM> clears flap <NUM>, flap <NUM> may return to a closed position, for example via the biasing force of the hinge <NUM>. While flap <NUM> sits in the closed position, flap <NUM> does not permit ball <NUM> to pass distally through the recessed portion of flap <NUM> or valve stem body <NUM>. This may be accomplished, for example, via a rim, shoulder or ledge in the proximal end of valve stem body <NUM> defined by a valve stem body <NUM> opening that is smaller than the outer circumferences of the flap <NUM>, so that an outer edge portion of flap <NUM> abuts the rim of the proximal end of the valve stem body <NUM> in the closed condition. The tether <NUM> may be continued to be pulled proximally to further tension the tether <NUM> until a desired tension on tether <NUM> is achieved between anchor <NUM> and valve <NUM>. The level of desired tension may be determined via any suitable method, including for example a display on the tensioning mechanism that outputs a tension force as the tether <NUM> is tensioned.

While the tether <NUM> is being tensioned, the contact between the balls <NUM> and the flap <NUM> may tend to pull the valve stem body <NUM>, and the connected prosthetic valve <NUM>, proximally in the direction that the tether <NUM> is being pulled. In some embodiments, the flap <NUM> may move freely enough that pulling the tether <NUM> does not tend to move the prosthetic valve <NUM>. For example, the frictional force between the expansion of the prosthetic valve <NUM> and the annulus of the native mitral valve <NUM> may be large enough to ensure that the force of the balls <NUM> pulling against flap <NUM> does not tend to move the prosthetic valve <NUM> in the direction that the tether <NUM> is being pulled. In other embodiments, a separate tool may be provided, for example as part of the delivery system, to contact the prosthetic valve <NUM> to provide a counteracting force to maintain the prosthetic valve <NUM> in the desired position as the tether <NUM> is pulled proximally. Once the tether <NUM> reaches the desired tension, tension on the tether <NUM> may be released, causing the tether <NUM> to tend to move distally through the valve stem body <NUM>. However, as noted above, the balls <NUM> of the tether <NUM> are unable to pass through the flap <NUM> in the distal direction since the flap <NUM> is in abutment with the proximal end of the valve stem body <NUM>. Thus, the contact between one of the balls <NUM> and the proximal face of flap <NUM> may result in tension being maintained and the flap <NUM> being maintained in the closed condition, particularly if the flap <NUM> is not actively biased toward the closed condition.

If it is determined that the tension on the tether <NUM> is too large, the tension may be relieved by any suitable mechanism. For example, a tool may be introduced via the delivery device (or a separate delivery device) to a position adjacent the valve stem body <NUM>, and the tool may be used to pull or otherwise hold flap <NUM> in the open position to allow balls <NUM> and tether <NUM> to pass distally through ball and flap mechanism <NUM> in order to reintroduce slack (or otherwise reduce tension) in tether <NUM> between valve <NUM> and anchor <NUM>. Whether or not the tension is readjusted in this manner, once the tension is at the final desired level and the tether <NUM> does not need to be further adjusted with respect to the ball and flap mechanism <NUM>, excess length of the tether proximal to the flap <NUM> may be removed by any suitable mechanism. For example, a tool may be utilized to cut the excess length of tether <NUM> extending proximally from valve <NUM> via cautery or mechanical cutting, with the entire length of the tether <NUM> proximal to the position of the cut to be removed from the patient.

<FIG> shows a tabbed valve stem <NUM>, which may provide similar functionality as the ball and flap mechanism <NUM> described above. In the illustrated embodiment, tabbed valve stem <NUM> may be substantially similar to connecting portion <NUM> described above, with certain exceptions. For example, tabbed valve stem <NUM> can be formed from a milled or laser-cut tube of a shape-memory material such as, for example, nitinol, similar or identical to that described above in connection with connecting portion <NUM>. Tabbed valve stem <NUM> may form a substantially cylindrical structure, and may include the micro-V's described above in connection with connecting portion <NUM>, or similar structures. However, while connecting portion <NUM> may form an entirely cylindrical passageway therethrough, tabbed valve stem <NUM> may include structures extending into the interior passage of the tabbed valve stem <NUM>. In the view of <FIG>, a cross-section of the tabbed valve stem <NUM> is illustrated with tether <NUM> passing therethrough. In the orientation of <FIG>, the bottom of the tabbed valve stem <NUM> represents the outflow end of the prosthetic valve, while the remainder of the inner frame <NUM>, which would extend from the top of the tabbed valve stem <NUM>, is omitted from the drawing. The other components of the prosthetic valve, such as the outer frame <NUM>, are also omitted from the figure for purposes of clarity. Tabs <NUM> may be laser cut into the nitinol tube portion <NUM> of tabbed valve stem <NUM>. For example, tabs <NUM> may be substantially "V"-shaped similar to the micro-V's described above. In the illustrated embodiment, tabs <NUM> are shaped so that the apex of the "V"-shape is pointed substantially in the proximal direction (toward the top of the page in the view of <FIG>) while the opposite end of the "V"-shape is pointed substantially in the distal direction (toward the bottom of the page in the view of <FIG>). In other words, the tabs <NUM> may be formed integrally with tubing <NUM>, although in other embodiments, the tabs <NUM> may be formed separately and attached to tubing <NUM>. Although a substantial "V"-shape is described, other shapes may be suitable, including linear bar shapes, or any other suitable shape. The tabs <NUM> may each be shape set such that, in the absence of applied forces, tabs <NUM> form an angle transverse to tubing <NUM>. While in this shape set condition, the ends of tabs <NUM> facing radially inward may point in a generally proximal direction, while the ends of tabs <NUM> facing radially outward may point in a generally distal direction. Tabbed valve system <NUM> may function in a similar fashion to ball and flap mechanism <NUM> described above. For example, tether <NUM> may be similar or identical to tether <NUM> and may similarly include balls <NUM> spaced along tether <NUM>. The delivery of the prosthetic valve <NUM> may be substantially identical as described above in connection with ball and flap mechanism <NUM>. For example, when tension is applied to the tether <NUM> by pulling the tether <NUM> proximally, tabs <NUM> may pivot about their connection to tubing <NUM> to separate, permitting balls <NUM> to pass beyond the tabs <NUM>. In one example, the tabs <NUM> may be pivotably connected to tubing <NUM> at a point nearer the distal end of the tabs <NUM> than the proximal end of the tabs <NUM>. When in the set shape, in the absence of applied forces, the distance between the proximal ends of the tabs <NUM> may be smaller than the diameter of the balls <NUM>, but larger than the diameter of the portions of tether <NUM> between adjacent balls <NUM>. Thus, as the tether <NUM> moves proximally relative to the tabs <NUM>, the balls <NUM> will cause the tabs <NUM> to separate. After ball <NUM> has completely cleared or passed tabs <NUM>, tabs <NUM> may return to a resting position, for example against tether <NUM>. When the pulling force on tether <NUM> is released, and the tether <NUM> is tensioned, the tether <NUM> will tend to try to move distally with respect to tabs <NUM> to release the tension. However, due to their set shape, the tabs <NUM> will not permit balls <NUM> to move distally past tabs <NUM>. Proximal pulling of the tether <NUM> may continue until a desired tension on tether <NUM> is reached between anchor <NUM> and valve <NUM>. Then, upon releasing the tether <NUM>, the tabs <NUM> will maintain the tether <NUM> in or near the desired tension by preventing distal movement of the tether <NUM> relative to the tabs <NUM>. The ends of tabs <NUM> facing radially outward (or generally distally) may extend radially beyond the outer perimeter of the tubing <NUM>, such that the outward ends of tabs <NUM> may be compressed to force tabs <NUM> to pivot into the substantially open position in order to allow balls <NUM> to translate distally through tubing <NUM> to reintroduce slack in tether <NUM> between valve <NUM> and anchor <NUM>. A tool may be utilized to cut excess tether <NUM> extending proximally from valve <NUM> via cautery or mechanical cutting, with the entire length of the tether <NUM> proximal to the position of the cut to be removed from the patient.

<FIG> show a barbed valve stem <NUM>, which may be provided on prosthetic valve <NUM> as an alternate embodiment of tether connecting portion <NUM>. Although the remainder of prosthetic heart valve <NUM> is omitted from <FIG>, it should be understood that barbed valve stem <NUM> is positioned at or near the outflow end of the prosthetic valve <NUM> (toward the bottom in the view of <FIG>), while the remainder of the valve would be positioned above the barbed valve stem <NUM> in the view of <FIG>. Barbed valve stem <NUM> can be formed from a milled or laser-cut tube of a shape-memory material such as, for example, nitinol. Preferably, barbed valve stem <NUM> is formed integrally with the inner frame <NUM>, although in some embodiments, the barbed valve stem <NUM> may be formed separately and attached to inner frame <NUM>. Barbed valve stem <NUM> may be cut into diamond cells that allow it to compress and expand, for example via self-expansion via shape-memory material properties or via mechanical compression or expansion via a suitable mechanical device.

Barbed valve stem is shown in <FIG> as if unrolled into a flat sheet for ease of illustration, although it should be understood that, in practice, the barbed valve stem <NUM> is generally tubular. In <FIG>, barbed valve stem <NUM> is illustrated in an axially collapsed, radially expanded condition. This condition may also correspond to the delivery condition of the prosthetic valve <NUM>. It should be noted that, although the barbed valve stem <NUM> is in an axially collapsed, radially expanded condition during delivery, the remainder of the prosthetic valve <NUM> is in an axially expanded, radially collapsed condition during delivery. Even when the barbed valve stem <NUM> is in a radially expanded condition, the diameter or profile of the barbed valve stem <NUM> is smaller than the diameter of the remainder of the prosthetic valve <NUM> while the remainder of the prosthetic valve <NUM> is in the radially collapsed condition. As a result, maintaining the barbed valve stem <NUM> in a radially expanded condition during delivery does not negatively affect the overall delivery profile of the prosthetic valve <NUM>. Barbed valve stem <NUM> may be shape set as to tend to transition to the radially collapsed condition shown in <FIG>. Thus, the barbed valve stem <NUM> may need to be maintained or held in the radially expanded condition during delivery of the prosthetic valve <NUM>. One mechanism by which the barbed valve stem <NUM> may be maintained in the radially expanded condition (or the axially collapsed condition) is at least one suture loop <NUM> which may loop around points of barbed valve stem <NUM> and extend proximally to be accessible to a surgeon. In the illustrated example, barbed valve stem <NUM> is maintained in the radially expanded condition by three suture loops <NUM>, with each suture loop having two free ends that extend through the delivery system. For example, each suture loop <NUM> may have a middle portion that loops one or more times around apices of diamond-shaped cells to axially compress those cells. In one example, each suture loop may loop through a distal-most and proximal-most cell in the barbed valve stem <NUM>. The suture loops <NUM> may be forced into a relatively small loop circumference in order to draw the cells closer together, and thus maintain the barbed valve stem <NUM> in the axially compressed (and radially expanded) condition. The barbed valve stem <NUM> may include a plurality of barbs <NUM> that have a first end connected to the barbed valve stem <NUM> and a second free end opposite the first end. The second free end of the barbs <NUM> may be sharp or pointed in order to allow the barbs <NUM> to pierce the tether. In the illustrated embodiment, each barb <NUM> is connected to the barbed valve stem <NUM> at intersections of adjacent cells. The barbs <NUM> are preferably integral with the barbed valve stem <NUM>, for example via laser cutting the entire barbed valve stem <NUM>, including barbs <NUM>, from a tube of nitinol or other suitable metal. The barbs <NUM> are also preferably shape set so that, in the absence of applied forces, they tend to point radially inwardly and proximally. With this configuration, a tether may be able to slide proximally relative to the barbed valve stem <NUM>, even when the barbs <NUM> are in contact with the tether. However, the barbs <NUM> may engage and/or pierce the tether when the tether tries to slide distally relative to the barbed valve stem <NUM> when the barbs <NUM> are in contact with the tether. Alternatively, barbed valve stem <NUM> may fixedly attach to the tether when the barbed valve stem <NUM> is radially compressed and the barbs <NUM> engage or pierce the tether, such contact between the barbs <NUM> and the tether prohibiting the prosthetic valve <NUM> from translating in either direction relative to the tether. When forced into the axially compressed state, the diameter of barbed valve stem <NUM> may increase, resulting in the sharp free ends of the barbs <NUM> being spaced apart from the tether. Thus, in this axially compressed condition, a tether passing through the barbed valve stem <NUM> will not contact (or will not significantly contact) the barbs <NUM> enough to cause the barbs <NUM> to engage or pierce the tether. This allows the tether to translate proximally or distally relative to the barbed valve stem <NUM> when the barbed valve stem <NUM> is in the radially expanded condition without the barbs <NUM> significantly hindering such movement.

Barbed valve stem <NUM> is shown in an axially expanded, radially collapsed, deployed condition in the flattened view of <FIG>. As noted above, barbed valve stem <NUM> may be at rest (or have its set shape) when in the radially collapsed state, and may have an inner diameter smaller than (or about equal to) that of the outer diameter of tether to bring the second free ends of the barbs <NUM> into contact with the tether. During delivery, the suture loops <NUM> may remain in place (and maintain the barbed valve stem <NUM> in the radially expanded condition) until prosthetic valve <NUM> has been positioned at the desired location within the native mitral valve annulus and the desired tension of the tether between anchor <NUM> and prosthetic valve <NUM> has been achieved. With the prosthetic valve <NUM> otherwise in its final desired condition, the suture loop(s) <NUM> may be released, allowing the barbed valve stem <NUM> to axially expand and radially collapse, bringing the sharp ends of the barbs <NUM> into contact with the tether. The suture loops <NUM> may be released by releasing the grip on one of the free ends of the suture loops <NUM>, and pulling the other free end of the suture loop <NUM> proximally. As the one free end of the suture loop <NUM> is pulled, the other free end of the suture loop <NUM> travels toward the barbed valve stem <NUM>, causing the loops or turns around the cells of the barbed valve stem <NUM> to unravel or uncoil, and eventually the released free end of the suture loop <NUM> will pull back through the delivery device and outside of the patient. After the suture loops <NUM> are released and the barbed valve stem <NUM> radially collapses, the pulling force on the tether that maintains the tether in the tensioned condition may be released. Upon release of that pulling force, the tether will tend to try to translate distally with respect to the barbed valve stem <NUM> to release the tension. However, because the sharp ends of the barbs <NUM> are in contact with the tether, the barbs will engage or pierce the tether (which may be formed of a relatively soft fabric and/or polymer) preventing the tether from translating any significant distance in the distal direction. While the barbs <NUM> engage the tether, the tension on the tether is maintained at or near the desired level, and the tether is prevented from translating distally relative to the prosthetic valve <NUM>. If it becomes necessary to release the barbs <NUM> from the tether, for example to re-position or remove the prosthetic valve <NUM>, a tool may be introduced to axially compress barbed valve stem <NUM> to force the barbed valve stem <NUM> to radially expand, moving the barbs <NUM> out of engagement with the tether.

<FIG> show guy-line tensioner <NUM>, which may be used with prosthetic valve <NUM>, either in addition to tether connecting portion <NUM>, or an alternate embodiment of tether connecting portion <NUM>. Guy-line tensioner <NUM> may include a tether <NUM> that is fixed to prosthetic valve <NUM> at or near the outflow end of the prosthetic valve <NUM>. For example, a first end of the tether <NUM> may be fixed to tether connecting portion <NUM> or to a similar structure. The tether <NUM> may be threaded through a tension clip <NUM>, for example through a first hole or aperture in the tension clip <NUM>. In one embodiment, the tension clip <NUM> has a substantially rectangular or oval shape, although other shapes may be suitable. The tension clip <NUM> may include relatively large front and back faces, with a first aperture extending through the tension clip <NUM> from the front face to the back face near a first end of the tension clip <NUM>. The tension clip <NUM> may include a second aperture extending through the tension clip <NUM> from the front face to the back face near a second end of the tension clip <NUM> opposite the first end. After the tether <NUM> passes through the first aperture, it may then loop around pad pulley <NUM>, with the second end <NUM> of the tether <NUM> fixed to tension clip <NUM>. Tension clip <NUM> may be configured such that when tension clip <NUM> is substantially parallel to a longitudinal axis of the prosthetic valve <NUM>, a relatively large amount of friction exists between tether <NUM> and tension clip <NUM>, the friction being large enough to prevent translation of tether <NUM> through tension clip <NUM>. This is the condition illustrated in <FIG>.

As shown in <FIG>, tension clip <NUM> may also be configured to be lifted and/or adjusted by one or more suture loops <NUM> such that tension clip <NUM> is no longer substantially parallel to the longitudinal axis of the prosthetic valve <NUM>. Each suture loop <NUM> may have two free ends and a middle portion therebetween, with the middle portion wrapping or looping around a corresponding aperture or other loop-receiving structure in tension clip <NUM>. As is described in greater detail below, as the tension clip <NUM> is adjusted from the position shown in <FIG> toward the position shown in <FIG>, friction between the tether <NUM> and the tension clip <NUM> reduces, allowing for the tension clip <NUM> to translate toward the prosthetic valve <NUM>, or alternatively allowing the prosthetic valve <NUM> to translate toward the tension clip <NUM>. Thus, with tension clip <NUM> in an adjusted position, friction may decrease between tether <NUM> and tension clip <NUM>, allowing tether <NUM> to translate through tension clip <NUM> to modify tension on tether <NUM>. In the illustrated embodiment, guy-line tensioner <NUM> includes a first suture loop <NUM> for adjusting the orientation of tension clip <NUM> to modify the friction between the tension clip <NUM> and the tether <NUM>, and a second suture loop <NUM> for translating the tension clip <NUM> along tether <NUM> for increasing or decreasing tension in the tether. Tension in the tether <NUM> may be sufficient to translate the tension clip <NUM> without any manipulation of the second suture loop <NUM> when the tension clip <NUM> is in an adjusted position. For example, modifying the tension clip <NUM> from its resting position to an adjusted position may release tension in the tether <NUM>, and tension on the second suture loop <NUM> may be exerted to preserve a desired level of tension on the tether <NUM>. In order to assist in changing the orientation of the tension clip <NUM>, the suture loop <NUM> for adjusting orientation is preferably connected to the tension clip <NUM> near where the second end <NUM> of the tether <NUM> couples to the tension clip <NUM>. In order to assist in translating the tension clip <NUM> to modify the tension of the tether <NUM>, the suture loop <NUM> for modifying tension is preferably connected to the tension clip <NUM> close to where the tether <NUM> passes through the tension clip <NUM>.

Anchor <NUM> may be deployed around the exterior surface of ventricular wall <NUM>, in a fashion similar or identical to the a method described above, with the tether <NUM> already passing through the tension clip <NUM>, wrapping around the pad pulley <NUM>, and the second end <NUM> of the tether <NUM> already affixed to the tension clip <NUM>. The pad pulley <NUM> may take the form of a rotatable pulley structure, or a static low friction surface around which the tether <NUM> wraps or loops. The pad pulley <NUM> functions to serve as an anchor point for the tether <NUM> while allowing (or at least not inhibiting) movement of the tether <NUM> during tension modification. The suture loops <NUM> may also be attached to the tension clip <NUM> prior to delivery and remain in place until the anchor <NUM> and the prosthetic valve <NUM> have both been deployed. Upon initial deployment of the prosthetic valve <NUM>, the tension clip <NUM> may be positioned with respect to tether <NUM> so that the tether <NUM> has enough slack to ensure that the prosthetic valve <NUM> is able to be positioned within the native valve annulus while the anchor <NUM> is deployed. After the initial deployment of the prosthetic valve <NUM> and the confirmation of the desired positioning, the tether <NUM> may be tensioned to the desired amount. In order to tension the tether <NUM>, the suture loop <NUM> for adjusting the orientation of the tension clip <NUM> may be pulled proximally, transitioning the tension clip <NUM> from the orientation shown in <FIG> to the orientation shown in <FIG>. As noted above, when tension clip <NUM> is angled at or near orthogonal to the longitudinal axis of the prosthetic valve <NUM> (as shown in <FIG>), friction between the tether <NUM> and the tension clip <NUM> where the tether <NUM> passes through the tension clip <NUM> is reduced compared to when the tension clip <NUM> is substantially parallel to the longitudinal axis of the prosthetic valve <NUM>. While the orientation of the tension clip <NUM> is maintained in the orientation shown in <FIG>, the other suture loop <NUM>, which is connected to the tension clip <NUM> near where the tether <NUM> passes through the tension clip <NUM>, may be pulled proximally. Proximal pulling of this suture loop <NUM> will tend to draw the tension clip <NUM> toward the prosthetic valve <NUM>. Since both ends of the tether <NUM> are fixed, as the tension clip <NUM> translates toward the prosthetic valve <NUM>, tension on the tether <NUM> increases. Once the desired tension of tether <NUM> between anchor <NUM> and valve <NUM> has been achieved, the suture loops <NUM> connected to tension clip <NUM> near the second end <NUM> of the tether <NUM> may be released, allowing the tension clip to again change orientation, from the orientation shown in <FIG> to the orientation shown in <FIG>. In the orientation of <FIG>, the friction between tether <NUM> and tension clip <NUM> increases, such that the force due to friction is larger than the force due to tension, resulting in the tension clip <NUM> maintaining its position so that the tether <NUM> remains at the desired tension. Then, the other suture loop <NUM> may also be released, for example by pulling one end of suture loop <NUM> proximally until it vacates the patient's body. After both suture loops <NUM> are released and withdrawn from the patient's body, as shown in <FIG>, tension clip <NUM> is in a resting position where tension clip <NUM> is substantially parallel to the longitudinal axis of prosthetic valve <NUM>, preventing tether <NUM> from translating through tension clip <NUM> while maintaining a consistent distance with desired tension in tether <NUM> between valve <NUM> and anchor <NUM>.

<FIG> show a clutch mechanism <NUM>, an alternative mechanism for securing a tether at a desired tension. The clutch mechanism <NUM> could be provided within (or adjacent to) tether connecting portion <NUM> of inner frame <NUM>, or as an alternative to tether connecting portion <NUM>. Clutch mechanism <NUM> may be substantially similar in function to butterfly clutch pin backs. Clutch mechanism <NUM> may include a substantially flat, annular base <NUM> that defines an opening through which tether <NUM> is configured to pass. When the tether <NUM> passes through the annular base <NUM> of the clutch mechanism <NUM>, the base <NUM> circumscribes tether <NUM>. The clutch mechanism <NUM> may include plates <NUM> extending in the outflow direction from the annular base <NUM> of clutch mechanism <NUM>. When there is no force applied to the plates <NUM>, the plates <NUM> may have free ends that point radially inwardly toward tether <NUM>. Each respective plate <NUM> may be operably coupled, for example via a hinge, to a corresponding wing <NUM>. Each wing <NUM> may extend in the inflow direction from the annular base <NUM> of clutch mechanism <NUM>. Each wing <NUM> may be operably coupled to its respective plate <NUM> such that movement of wings <NUM> causes corresponding movement of plates <NUM>. Tether <NUM> may include balls <NUM> spaced along tether <NUM> similar or identical to embodiments described above. Plates <NUM> may be positioned such that, in a resting state, the distance between plates <NUM> at their free ends is less than the diameter of ball <NUM>, but greater than or equal to the diameter of the portions of tether <NUM> between adjacent balls <NUM>, preventing tether <NUM> from translating through clutch mechanism <NUM> when the plates <NUM> are in their resting or closed position. Wings <NUM> may be configured such that when wings <NUM> are pinched or compressed to move the free ends of the wings <NUM> toward a longitudinal center of the clutch mechanism <NUM>, the free ends of the plates <NUM> pivot radially outwardly to increase the distance between the plates <NUM> at their free ends. Movement of the wings <NUM> may be configured to cause a corresponding increase in distance between plates <NUM> at their free ends to surpass the diameter of ball <NUM>, allowing tether <NUM> and associated balls <NUM> to translate through clutch mechanism <NUM>, uninhibited by plates <NUM>. Each wing <NUM> may include suture loop <NUM>. Suture loop <NUM> may loop around wing <NUM>, or a structure attached to wing <NUM> fit to receive suture loop <NUM>, and extend proximally to be accessible to a surgeon, in a fashion substantially similar to other suture loops described herein. During tensioning of the tether <NUM>, the suture loops <NUM> may be pulled proximally to compress or pinch the wings <NUM>, and thus increase the distance between the free ends of plates <NUM>. The tether <NUM> may be tensioned a desired amount, and the force on the wings <NUM> via suture loops <NUM> may be reduced so that the plates <NUM> move back to their resting configuration, inhibiting further movement of the tether <NUM> via contact between the balls <NUM> and the plates <NUM>. Suture loops <NUM> may remain in place until valve <NUM> has been positioned and desired tension of tether <NUM> between anchor <NUM> and prosthetic valve <NUM> has been achieved. Suture loops <NUM> may then be released by pulling one end of suture loop <NUM> proximally until it vacates the patient's body. If it becomes desirable or necessary to adjust the tension of the tether <NUM> after the suture loops <NUM> have been removed from the patient, a separate tool may be introduced into the patient to compress or pinch wings <NUM>, allowing for additional adjustment of the tension of the tether <NUM>.

<FIG> illustrates valve <NUM> implanted in heart <NUM> with anchor <NUM> seated at or near apex <NUM> of heart <NUM>. In the illustrated example, desired tension of tether <NUM> between valve <NUM> and anchor <NUM> has been achieved, and excess tether <NUM> extending proximally from valve <NUM> is cut and removed from the patient, leaving affixed valve <NUM> and properly tensioned tether <NUM> behind.

Claim 1:
A prosthetic heart valve system comprising:
a prosthetic heart valve (<NUM>) having an expandable stent (<NUM>) and a prosthetic valve assembly (<NUM>) disposed within the stent (<NUM>), the prosthetic valve assembly (<NUM>) configured to allow blood to flow in a direction from an inflow end of the stent (<NUM>) toward an outflow end of the stent (<NUM>) and to substantially block blood from flowing from the outflow end of the stent (<NUM>) toward the inflow end of the stent, the prosthetic heart valve including a tether connecting portion (<NUM>);
a collapsible and expandable anchor (<NUM>) adapted to be disposed on or adjacent an epicardial surface of a heart (<NUM>) of a patient; and
a tether (<NUM>) having a distal end coupled to the anchor (<NUM>), the tether (<NUM>) extending proximally from the anchor (<NUM>), the tether (<NUM>) defining a protrusion (<NUM>) having a width greater than portions of the tether (<NUM>) adjacent the protrusion (<NUM>),
wherein the prosthetic heart valve (<NUM>) is configured to translate along the tether (<NUM>) toward the distal end of the tether (<NUM>), the protrusion (<NUM>) of the tether configured to engage the tether connecting portion (<NUM>) to prevent proximal movement of the prosthetic heart valve (<NUM>) relative to the tether (<NUM>).