Patent Description:
The heart of vertebrate animals is divided into four chambers, and is equipped with four valves (the mitral, aortic, pulmonary and tricuspid valves) that ensure that blood pumped by the heart flows in a forward direction through the cardiovascular system without backflow. The mitral valve of a healthy heart prevents the backflow of blood from the left ventricle into the left atrium of the heart, and comprises two flexible leaflets (anterior and posterior) that close when the left ventricle contracts. The leaflets are attached to a fibrous annulus, and their free edges are tethered by subvalvular chordae tendineae to papillary muscles in the left ventricle to prevent them from prolapsing into the left atrium during the contraction of the left ventricle.

Various cardiac diseases or degenerative changes may cause dysfunction in any of these portions of the mitral valve apparatus, causing the mitral valve to become abnormally narrowed or dilated, or to allow blood to leak (also referred to as regurgitate) from the left ventricle back into the left atrium. Any such impairments compromise cardiac sufficiency, and can be debilitating or life threatening.

Numerous surgical methods and devices have accordingly been developed to treat mitral valve dysfunction, including open-heart surgical techniques for replacing, repairing or reshaping the native mitral valve apparatus, and the surgical implantation of various prosthetic devices such as annuloplasty rings to modify the anatomy of the native mitral valve. More recently, less invasive transcatheter techniques for the delivery of replacement mitral valve assemblies have been developed. In such techniques, a prosthetic valve is generally mounted in a crimped state on the end of a flexible catheter and advanced through a blood vessel or the body of the patient until the valve reaches the implantation site. The prosthetic valve is then expanded to its functional size at the site of the defective native valve.

<CIT> describes an inflatable cardiovascular prosthetic implant. The implant has two inner rings that support a one-way valve that allows flow through the implant. The implant has an outer ring positioned between the two inner rings and radially extending beyond the two inner rings. The implant has anchors that attach to heart tissue to help seal the implant in the annulus of the native valve. As shown in <FIG> and <FIG>, a hoop structure connects the first anchor to the second anchor. The first and the second anchors are moveable between an extended configuration and a deployed configuration. The hoop structure receives a first torque from the first anchor wherein the first anchor moves from the extended configuration to the deployed configuration. The hoop structure receives a second torque from the second anchor when the second anchor moves from the extended configuration to the deployed configuration. The first torque counteracts the second torque.

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views or similar steps. The drawings illustrate generally, by way of example, but not by way of limitation, various examples discussed in the present document.

While some of the surgical and less invasive treatments for valvar regurgitation are promising, they can be difficult to deliver, expensive to manufacture, or may not be indicated for all patients. Therefore, it would be desirable to provide improved devices and methods for the treatment of valvar insufficiency such as mitral insufficiency. At least some of these objectives will be met by the devices and methods disclosed.

Specific examples of the disclosed device, delivery system, and method will now be described with reference to the drawings. Nothing in this detailed description is intended to imply that any particular component, feature, or step is essential to the invention.

The left ventricle LV of a normal heart H in systole is illustrated in <FIG>. The left ventricle LV is contracting and blood flows outwardly through the aortic valve AV which is a tricuspid valve, in the direction of the arrows. Back flow of blood or "regurgitation" through the mitral valve MV is prevented since the mitral valve is configured as a "check valve" which prevents back flow when pressure in the left ventricle is higher than that in the left atrium LA. The mitral valve MV comprises a pair of leaflets having free edges FE which meet evenly to close, as illustrated in <FIG>. The opposite ends of the leaflets LF are attached to the surrounding heart structure along an annular region referred to as the annulus AN. The free edges FE of the leaflets LF are secured to the lower portions of the left ventricle LV through chordae tendineae CT (also referred to herein as the chordae) which include a plurality of branching tendons secured over the lower surfaces of each of the valve leaflets LF. The chordae CT in turn, are attached to the papillary muscles PM which extend upwardly from the lower portions of the left ventricle and interventricular septum IVS.

Referring now to <FIG>, a number of structural defects in the heart can cause mitral prolapse since inadequate tension is transmitted to the leaflet via the chordae. While the other leaflet LF1 maintains a normal profile, the two valve leaflets do not properly meet and leakage from the left ventricle LV into the left atrium LA will occur, as shown by the arrow.

Regurgitation also occurs in the patients suffering from cardiomyopathy where the heart is dilated and the increased size prevents the valve leaflets LF from meeting properly, as shown in <FIG>. The enlargement of the heart causes the mitral annulus to become enlarged, making it impossible for the free edges FE to meet during systole. The free edges of the anterior and posterior leaflets normally meet along a line of coaptation C as shown in <FIG>, but a significant gap G can be left in patients suffering from cardiomyopathy, as shown in <FIG>.

Mitral valve regurgitation can also occur in patients who have suffered ischemic heart disease where the functioning of the papillary muscles PM is impaired, as illustrated in <FIG>. As the left ventricle LV contracts during systole, the papillary muscles PM do not contract sufficiently to effect proper closure. The leaflets LF1 and LF2 then prolapse, as illustrated. Leakage again occurs from the left ventricle LV to the left atrium LA, as shown by the arrow.

<FIG> more clearly illustrates the anatomy of a mitral valve MV which is a bicuspid valve having an anterior side ANT and a posterior side POST. The valve includes an anterior (aortic) leaflet AL and a posterior (mural) leaflet PL. Chordae tendineae CT couple the valve leaflets AL, PL with the antero-lateral papillary muscle ALPM and the postero-medial papillary muscle PMPM. The valve leaflets AL, PL join one another along a line referred to as the antero-lateral commissure ALC and the posterior-medial commissure PMC. The annulus AN circumscribes the valve leaflets, and two regions adjacent an anterior portion of the annulus, on opposite sides of the anterior leaflet are referred to as the left fibrous trigone LFT and also the right fibrous trigone RFT. These areas are indicted by generally by the solid triangles. <FIG> more clearly illustrates the left and right fibrous trigones, LFT, RFT.

While various surgical techniques as well as implantable devices have been proposed and appear to be promising treatments for mitral regurgitation, surgical approaches can require a lengthy recovery period, and implantable devices have varying clinical results. Therefore, there still is a need for improved devices and methods for treating mitral regurgitation. While the examples disclosed herein are directed to an implantable prosthetic mitral valve for treating mitral regurgitation, one of skill in the art will appreciate that this is not intended to be limiting, and the device and methods disclosed herein may also be used to treat other valves such as cardiac valves like the tricuspid valve, aortic valve, pulmonary valve, etc, as well as other valves in the body such as venous valves.

Prosthetic valves have been surgically implanted in the heart as a treatment for mitral regurgitation. Some of these valves have been valves harvested from animals such as porcine valves, and others have been prosthetic mechanical valves with or without a tissue covering. More recently, minimally invasive catheter technology has been used to deliver prosthetic valves to the heart. These valves typically include an anchor for securing the valve to the patient's heart, and a valve mechanism, either a mechanical valve, a valve with animal tissue or a synthetic material, or combinations thereof. The prosthetic valve once implanted, takes over for malfunctioning native valve, thereby reducing or eliminating valvar insufficiency. While some of these valves appear promising, there still is a need for improved valves. The following discloses examples of a prosthetic valve, a delivery system for the prosthetic valve, and methods of delivering the valve that may overcome some of the challenges associated with existing prosthetic valves.

Referring now to <FIG>, examples of a mitral valve prosthesis generally designated with reference numeral <NUM> comprise tricuspid tissue-type prosthetic one-way valve structure <NUM> comprising leaflets <NUM> affixed within self-expanding or expandable anchor portion <NUM> having a geometry that expands into low profile atrial skirt region <NUM>, annular region <NUM>, ventricular skirt region <NUM>, and a plurality of leaflet commissures <NUM> (also referred to herein as commissure posts) extending axially in a cantilevered fashion downstream into the sub-annular space defined by ventricular skirt region <NUM>.

<FIG> shows a partial cross-section of the valve <NUM> from the patient's left ventricle looking upward toward the right atrium. The atrial skirt region <NUM> is anchored to a lower portion of the right atrium <NUM>. The valve leaflets <NUM> have an open position (not illustrated) and a closed position illustrated in <FIG>. In the open position, the leaflets <NUM> are displaced away from one another to allow blood flow therepast, and in the closed position, the leaflets <NUM> engage one another to close the valve and prevent retrograde blood flow therepast. The valve commissures <NUM> may be configured to optimize the efficiency of the prosthetic valve structure <NUM> and the load distribution on the leaflets <NUM> by providing for the attachment of the leaflets <NUM> along arcuate seams <NUM> (best seen in <FIG>), and by being made selectively flexible at different points or zones along their axial length through the addition/deletion of reinforcing struts.

<FIG> shows a perspective view of the anchor portion <NUM> of the valve <NUM> which has been formed from a series of interconnected struts. The atrial skirt region <NUM> forms an annular flanged region on the anchor to help secure an upper portion of the prosthetic valve in the atrium, and the annular region <NUM> is a cylindrical region for anchoring the valve along the native valve annulus. The ventricular skirt region <NUM> similarly is cylindrically shaped and helps anchor a lower portion of the valve in the patient's left ventricle. Any portion, or all of the anchor may be covered with tissue such as pericardium or other tissues disclosed herein, or a synthetic material such as Dacron or ePTFE may be used to cover the anchor. The covering helps to seal the anchor to the native valve, and this helps funnel blood into and through the prosthetic valve, rather than around the valve. In some examples, the anchor may remain uncovered. The prosthetic valve has an expanded configuration and a collapsed configuration. The collapsed configuration has a low profile cylindrical shape that is suitable for mounting on a delivery system and delivery may be made either transluminally on a catheter, or transapically through the heart wall. The expanded configuration (as illustrated) allows the prosthetic valve to be anchored into a desired position.

<FIG> illustrates a perspective view of an example of a prosthetic mitral valve with optional coverings removed to allow visibility of the anchor struts. <FIG> illustrates a top view of the prosthetic valve in <FIG> from the atrium looking down into the ventricle. The valve <NUM> includes an asymmetrical expanded anchor portion having a D-shaped cross-section. As shown, the anchor portion generally comprises anterior <NUM> and posterior <NUM> aspects along the longitudinal axis thereof, as well as atrial <NUM>, annular <NUM> and ventricular <NUM> regions that correspond generally to the atrial skirt <NUM>, annular <NUM> and ventricular skirt <NUM> regions of the example described above in <FIG>. Commissures (also referred to herein as commissure posts) <NUM> also correspond generally to the leaflets <NUM> of the examples in <FIG>. The prosthetic valve <NUM> has a collapsed configuration and an expanded configuration. The collapsed configuration is adapted to loading on a shaft such as a delivery catheter for transluminal delivery to the heart, or on a shaft for transapical delivery through the heart wall. The radially expanded configuration is adapted to anchor the valve to the patient's native heart adjacent the diseased or damaged valve. In order to allow the valve to expand from the collapsed configuration to the expanded configuration, the anchor portion of the valve may be fabricated from a self-expanding material such as a nickel titanium alloy like nitinol, or it may also be made from spring temper stainless steel, or a resilient polymer. In still other examples, the anchor may be expandable with an expandable member such as a balloon. In any example, the anchor is fabricated by laser cutting, electrical discharge machining (EDM), or photochemically etching a tube such as hypodermic needle tubing. The anchor may also be fabricated by photochemically etching a flat sheet of material which is then rolled up with the opposing ends welded together.

The atrial skirt portion <NUM> forms a flanged region that helps to anchor the prosthetic valve to the atrium, above the mitral valve. The atrial skirt includes a plurality of triangular fingers which extend radially outward from the anchor to form the flange. The posterior <NUM> portion of the atrial skirt <NUM> is generally round or circular, while a portion of the anterior <NUM> part of the atrial skirt <NUM> is flat. Thus, the atrial skirt region may have a D-shaped cross-section. This allows the prosthetic valve to conform to the patient's cardiac anatomy without obstructing other portions of the heart, as will be discussed below. Each triangular finger is formed from a pair of interconnected struts. The triangular fingers of the atrial skirt generally are bent radially outward from the central axis of the prosthetic valve and lie in a plane that is transverse to the valve central axis. In some examples, the atrial skirt lies in a plane that is substantially perpendicular to the central axis of the valve. The anterior portion <NUM> of the atrial skirt <NUM> optionally includes an alignment element <NUM> which may be one or more struts which extend vertically upward and substantially parallel to the prosthetic valve. The alignment element <NUM> may include radiopaque markers (not illustrated) to facilitate visualization under fluoroscopy. The alignment element helps the physician to align the prosthetic valve with the native mitral valve anatomy, as will be discussed later.

Disposed under the atrial skirt region is the annular region <NUM> which also has a collapsed configuration for delivery, and an expanded configuration for anchoring the prosthetic valve along the native valve annulus. The annular region is also comprised of a plurality of interconnected struts that form a series of cells, either closed cells or open cells. Suture holes <NUM> in some of the struts allow tissue or other coverings (not illustrated) to be attached to the annular region. Covering all or a portion of the anchor with tissue or another covering helps seal the anchor against the heart valve and adjacent tissue, thereby ensuring that blood is funneled through the valve, and not around it. The annular region may be cylindrical, but in any example may have a posterior portion <NUM> which is circular, and an anterior portion <NUM> which is flat, thereby forming a D-shaped cross-section. This D-shaped cross-section conforms better to the native mitral valve anatomy without obstructing blood flow in other areas of the heart such as by impinging on the left ventricular outflow tract.

The lower portion of the prosthetic valve includes the ventricular skirt region <NUM>. The ventricular skirt region also has a collapsed configuration for delivery, and an expanded configuration for anchoring. It is formed from a plurality of interconnected struts that form a series of cells, that may be closed, that can radially expand. The ventricular skirt in the expanded configuration anchors the prosthetic valve to the ventricle by expanding against the native mitral valve leaflets. Optional barbs <NUM> in the ventricular skirt may be used to further help anchor the prosthetic valve into the ventricular tissue. Barbs may optionally also be included in the atrial skirt portion as well as the annular region of the anchor. Additionally, optional suture holes <NUM> in the ventricular skirt may be used to help suture tissue or another material to the ventricular skirt region, similarly as discussed above. The anterior <NUM> portion of the ventricular skirt may be flat, and the posterior <NUM> portion of the ventricular skirt may be circular, similarly forming a D-shaped cross-section to anchor and conform to the native anatomy without obstructing other portions of the heart. Also, the lower portions of the ventricular skirt serve as deployment control regions since the lower portions can remain sheathed thereby constraining the ventricular skirt from radial expansion until after the optional ventricular trigonal anchor tabs and posterior anchor tab have expanded, as will be explained in greater detail below.

The ventricular skirt portion may optionally also include a pair of ventricular trigonal tabs <NUM> on the anterior portion of the anchor (only <NUM> visible in this view) for helping to anchor the prosthetic valve as will be discussed in greater detail below. The ventricular skirt may also optionally include a posterior tab <NUM> on a posterior portion <NUM> of the ventricular skirt for anchoring the prosthetic valve to a posterior portion of the annulus. The trigonal tabs <NUM> or the posterior tab <NUM> are tabs that extend radially outward from the anchor, and they are inclined upward in the upstream direction.

The actual valve mechanism is formed from three commissure posts (also referred to as commissures) <NUM> which extend radially inward toward the central axis of the anchor in a funnel or cone-like shape. The commissures <NUM> are formed from a plurality of interconnected struts that create the triangular shaped commissures. The struts of the commissures may include one or more suture holes <NUM> that allow tissue or a synthetic material to be attached to the commissures. In this example, the valve is a tricuspid valve, therefore it includes three commissures <NUM>. The tips of the commissures may include a commissure tab <NUM> (also referred to as a tab) for engaging a delivery catheter. In this example, the tabs have enlarged head regions connected to a narrower neck, forming a mushroom-like shape. The commissures may be biased in any position, but may angle inward slightly toward the central axis of the prosthetic valve so that retrograde blood flow forces the commissures into apposition with one another to close the valve, and antegrade blood flow pushes the commissures radially outward, to fully open the valve. <FIG> is a top view illustrating the prosthetic valve of <FIG> from the atrial side, and shows the D-shaped cross-section.

<FIG> illustrates the prosthetic mitral valve of <FIG> with a covering <NUM> coupled to portions of the anchor with suture <NUM>. This view is taken from an atrial perspective. In this example, the covering may be pericardium which may come from a number of sources as disclosed elsewhere in this specification. In alternative examples, the covering may be a polymer such as Dacron polyester, ePTFE, or another synthetic material. The covering may be disposed over the annular region <NUM> and the ventricular skirt region <NUM>, and in some examples the anterior ventricular trigonal <NUM> tabs and the ventricular posterior tab <NUM> may also be covered with the same or a different material. The covering helps seal the anchor against the adjacent tissue so that blood funnels through the valve mechanism. In this example, the atrial skirt is left uncovered, as well as tabs <NUM>, <NUM> but they may be covered if desired. Additionally, radiopaque markers 814a form a portion of the alignment element and facilitate visualization of the prosthetic valve under fluoroscopy which is important during alignment of the valve.

<FIG> is a perspective view of the prosthetic mitral valve seen in <FIG>, as seen from the ventricle. The struts of the valve commissures are covered with the same material or a different material as the annular and ventricular regions as discussed above, thereby forming the tricuspid valve leaflets <NUM>. <FIG> shows the valve in the closed configuration where the three leaflets are engaged with one another preventing retrograde blood flow. Commissure tabs <NUM> remain uncovered and allow the commissures to be coupled with a delivery device as will be explained below. The prosthetic valve in <FIG> may be sterilized so they are suitable for implantation in a patient using methods known in the art.

<FIG> illustrates the prosthetic valve of <FIG> with the covering removed, and the remaining anchor unrolled and flattened out. The prosthetic valve <NUM> is formed from a plurality of interconnected struts. For example, the atrial skirt region <NUM> includes a plurality of interconnected struts that form a series of peaks and valleys. The flat anterior region <NUM> of the prosthetic valve has its peaks and valleys axially offset from those of the remaining portion of the atrial skirt, and this region becomes a part of the alignment element <NUM>. Radiopaque markers 814a are disposed on either side of the offset peaks and valleys and help with visualization during implantation of the valve. An axially oriented connector joins the struts of the skirt region <NUM> with the struts of the annular region <NUM>. The annular region is also comprised of a plurality of axially oriented and interconnected struts that form peaks and valleys. Connector struts couple struts of the annular region with the struts of the ventricular region <NUM>. The ventricular region also includes a plurality of interconnected struts that form peaks and valleys. Additionally, the struts form the leaflet commissures <NUM>, the ventricular skirt <NUM>, as well as the trigonal and posterior tabs <NUM>, <NUM>. Suture holes <NUM> are disposed along the struts of the annular region as well as the ventricular region to allow attachment of a cover such as pericardium or a polymer such as Dacron or ePTFE. Optional barbs <NUM> are disposed along the ventricular skirt <NUM> to help anchor the prosthetic valve to adjacent tissue.

Commissure tabs or tabs <NUM> are disposed on the tips of the commissures <NUM> and may be used to releasably couple the prosthetic valve with a delivery system as will be described below. One of skill in the art will appreciate that a number of strut geometries may be used, and additionally that strut dimensions such as length, width, thickness, etc. may be adjusted in order to provide the anchor with the desired mechanical properties such as stiffness, radial crush strength, commissure deflection, etc. Therefore, the illustrated geometry is not intended to be limiting.

Once the flat anchor pattern has been formed by EDM, laser cutting, photochemical etching, or other techniques known in the art, the anchor is radially expanded into a desired geometry. The anchor is then heat treated using known processes to set the shape. Thus, the anchor may be loaded onto a delivery catheter in a collapsed configuration and constrained in the collapsed configuration with a constraining sheath. Removal of the constraining sheath will allow the anchor to self-expand into its unbiased pre-set shape. In other examples, an expandable member such as a balloon may be used to radially expand the anchor into its expanded configuration.

<FIG> show a delivery apparatus <NUM> fashioned to deliver a prosthetic mitral valve to the heart transapically. However, one of skill in the art will appreciate that the delivery system may be modified and relative motion of the various components adjusted to allow the device to be used to deliver a prosthetic mitral valve transseptally. The delivery apparatus is generally comprised of a handle <NUM> that is the combination of a handle section <NUM> and a handle section <NUM> (best seen in <FIG>), as well as a flexible tip <NUM> that can smoothly penetrate the apex of the heart, and a sheath catheter <NUM> which houses several additional catheters that are designed to translate axially and will be described in detail below.

The handle <NUM> includes a female threaded Luer adaptor <NUM> which connects to a Tuohy Borst adaptor <NUM> in order to provide a hemostatic seal with a <NUM>" diameter guide wire (not shown). The female threaded Luer adaptor <NUM> is in threaded contact with the proximal section of the handle <NUM> through a threaded port <NUM> (best seen in <FIG>).

As can be seen in <FIG>, the handle <NUM> provides location for the control mechanisms used to position and deploy a prosthetic mitral valve. The handle <NUM> provides housing for a thumbwheel <NUM> that can be accessed through a window <NUM> that appears on both the top and bottom of the handle <NUM>. The thumbwheel <NUM> internally mates with a threaded insert <NUM> (best seen in <FIG>) that actuates the sheath catheter <NUM>, and the mechanics of this interaction will be explained in detail below.

<FIG> also shows a deployment thumbwheel <NUM> that provides linear translation to a deployment catheter <NUM> (best seen in <FIG>) when turned, since the turning motion of the deployment thumbwheel <NUM> acts as a power screw, pushing the peg <NUM> forward and distally from the user. The mechanics behind the peg <NUM> will be further detailed below. The thumbwheel lock <NUM> provides a security measure against unwanted rotation of the deployment thumbwheel <NUM> by acting as a physical barrier to rotation. In order to turn the deployment thumbwheel <NUM> the user must push forward the thumbwheel lock <NUM>, disengaging it from two slots <NUM> (seen in <FIG>) in the deployment thumbwheel <NUM>.

As can also be seen in <FIG>, a bleed valve <NUM> and fluid line <NUM> are connected to an internal mechanism in the distal portion of the handle <NUM>, which provides a hemostatic seal for the sheath catheter <NUM>. The details of this connection will be described below.

Internal mechanics of the delivery apparatus <NUM> are illustrated in detail in <FIG>, and the following descriptions will reveal the interactions between individual components, and the manner in which those components combine in order to achieve a prosthetic heart valve delivery apparatus.

As seen in <FIG>, a handle section <NUM> and handle section <NUM> combine to create a handle <NUM> that forms the basis of the delivery apparatus <NUM>. In order to advance the sheath catheter <NUM> during valve loading, or retract the sheath catheter <NUM> during deployment, a rotatable thumbwheel <NUM> is in threaded contact (internal threads <NUM> seen in <FIG>) with a threaded insert <NUM> (external threads <NUM> of <FIG>) that translates linearly along the axis of the delivery apparatus, from a proximal position to a distal position. The sheath catheter <NUM> is in mating contact with the threaded insert <NUM> and is fastened through the use of a collar <NUM> that aligns and mates the collar with the insert. The collar <NUM> is fastened with screws <NUM> (best seen in DETAIL A in <FIG>) to the threaded insert <NUM> and contains a fluid port <NUM> (best seen in DETAIL A in <FIG>) that provides location for the fluid line <NUM> so that hemostasis can be maintained between the patient and delivery apparatus. An O-ring <NUM> (best seen in DETAIL A in <FIG>) seals the stationary catheter <NUM> (best seen in <FIG>) against the sheath catheter <NUM>. The fluid line <NUM> also provides a means of visually locating the sheath catheter <NUM> with respect to position, as a slot <NUM> in the handle <NUM> allows the fluid line <NUM> to translate with the sheath catheter <NUM> (through a hole <NUM> (best seen in DETAIL A in <FIG>) during operation, and this translation is highly visible. In order to prevent rotation of the threaded insert during translation, a flat face <NUM> has been machined onto both sides of the threaded insert <NUM>. The flat faces <NUM> remain in contact with bosses <NUM> and <NUM> that are located on both handle section <NUM> and handle section <NUM> so that the bosses <NUM> and <NUM> act to grip the threaded insert <NUM> and prevent rotation. A textured pattern <NUM> allows the user to easily turn the thumbwheel <NUM> in the surgical field. Detents <NUM> (best seen in <FIG>) locate flanges <NUM> (seen in <FIG>) on the thumbwheel <NUM> in order to allow for rotation.

The manner in which individual catheters (there are four catheters) move with respect to each other is illustrated in <FIG>. Sheath catheter <NUM> provides housing for the stationary catheter <NUM>, which in turn provides housing for the movable hub catheter <NUM>. The hub catheter <NUM> translates linearly with respect to the nose catheter <NUM> which can also be translated with respect to each previous catheter, and the handle <NUM>. The stationary catheter <NUM> is mated to a handle section <NUM> in an internal bore <NUM> which also forms a seal between the stationary catheter <NUM> and the hub catheter <NUM>. The distal portion of the stationary catheter <NUM> is formed in the shape of a bell <NUM> (see DETAIL A in <FIG>) which acts as a housing to retain the hub capture <NUM> (seen in DETAIL A in <FIG>).

As previously stated a thumbwheel lock <NUM> prevents rotation of the deployment thumbwheel <NUM>. In order to provide a seating force that keeps the thumbwheel lock <NUM> in a locked position until manipulated, a spring <NUM> is housed in an internal bore <NUM> (best seen in <FIG>) and abuts against a shoulder <NUM> (best seen in <FIG>) that is located inside the thumbwheel lock <NUM>. This spring <NUM> maintains the leading edge <NUM> of the thumbwheel lock <NUM> in a locked position within the two slots <NUM> of the deployment thumbwheel <NUM>. Gripping texture <NUM> is provided on the thumbwheel lock <NUM> for ease of use. In order to locate and retain the thumbwheel lock <NUM> inside of the handle <NUM>, a slot <NUM> has been provided in both a handle section <NUM> and a handle section <NUM>.

As shown in <FIG>, a sliding block <NUM> is housed inside of flat parallel faces <NUM> which appear on the inside of the handle <NUM>. This sliding block <NUM> is in mating contact with hub catheter <NUM> and is the physical mechanism that linearly actuates the catheter. A spring <NUM> is mounted on an external post <NUM> and abuts against a shoulder <NUM> that is located on the distal end of the sliding block <NUM>. This spring <NUM> forces a peg <NUM> (located inside a thru-hole <NUM> of <FIG>) into contact with the proximal edge of an angled slot <NUM> that is cut into the deployment thumbwheel <NUM>. The deployment thumbwheel <NUM> is contained between a shoulder <NUM> and a snap ring (not shown), both of which are features of the handle <NUM>. Gripping texture <NUM> on the deployment thumbwheel <NUM> allows the user to easily rotate the thumbwheel in a clockwise direction, actuating the peg <NUM> to ride distally along the slot <NUM> and move the sliding block <NUM>, which pushes the hub catheter <NUM> and hub <NUM> (best seen in DETAIL A of <FIG>) forward and out of the bell <NUM> (seen in DETAIL A of <FIG>). A slot <NUM> appears in a handle section <NUM> and a handle section <NUM> and prevents the peg <NUM> from translating beyond a desired range.

A nose catheter <NUM> extends from a Tuohy Borst adaptor <NUM> on the proximal end of the handle <NUM>, and internally throughout the handle and the respective catheters (sheath catheter <NUM>, stationary catheter <NUM>, and hub catheter <NUM>), terminating inside the rigid insert <NUM> (seen in <FIG>) of the flexible tip <NUM> (seen in <FIG>) that abuts with the distal end of the sheath catheter <NUM>.

<FIG> displays an exploded view of the tip section of the delivery apparatus <NUM>, and shows the relation between prosthetic mitral valve <NUM> and the internal and external catheters. When crimped and loaded, the prosthetic mitral valve <NUM> is encased between the internal surface of the sheath catheter <NUM> and the external surface of the nose catheter <NUM>. In order to capture and anchor the prosthetic mitral valve <NUM> within the delivery apparatus <NUM>, three commissure tabs <NUM> (circumferentially spaced at about <NUM> degrees apart) appearing on the proximal end of the prosthetic mitral valve <NUM> provide points of contact between the valve and three slots <NUM> (seen in <FIG>) that are machined into the outer surface of the hub <NUM> (circumferentially spaced at about <NUM> degrees apart). After first advancing the hub catheter <NUM> (<FIG>) by rotating the deployment thumbwheel <NUM> (seen in <FIG>) clockwise, the three commissure tabs <NUM> can be captured within the three slots <NUM> (seen in <FIG>). The hub <NUM> can then be retracted into the bell <NUM> by releasing the deployment thumbwheel <NUM> (seen in <FIG>). In this position the prosthetic mitral valve <NUM> is anchored to the delivery apparatus <NUM>, and further crimping of the valve will allow the sheath catheter <NUM> to be advanced over the valve.

<FIG> further detail the manner in which loading of the prosthetic mitral valve <NUM> (seen in <FIG>) into the delivery apparatus <NUM> can be achieved. Initially, the flexible tip <NUM> is abutted against the distal edge <NUM> of the sheath catheter <NUM>. The flexible tip <NUM> is comprised of a rigid insert <NUM>, and a soft and flexible tip portion <NUM> which is over-molded onto the rigid insert <NUM>. The shoulder <NUM> and tapered face <NUM> of the rigid insert <NUM> act to guide and locate the distal edge <NUM> of the sheath catheter <NUM>, so that the catheter may rest against and be stiffened by the flexible tip <NUM>, and be more easily introduced into the apex of the heart.

An initial position from which loading can be achieved is illustrated in <FIG>. As a first step in the loading of a prosthetic mitral valve <NUM> (seen in <FIG>) into the delivery apparatus <NUM>, the sheath catheter <NUM> is withdrawn by rotation of the thumbwheel <NUM> in a clockwise direction. The distal edge <NUM> of the sheath catheter <NUM> is retracted until it passes the distal edge of the bell <NUM>, as illustrated in DETAIL A of <FIG>. As a second step in the loading of a prosthetic mitral valve <NUM> (seen in <FIG>) into the delivery apparatus <NUM>, the hub <NUM> is advanced from beneath the bell <NUM> by clockwise turning of the deployment thumbwheel <NUM> (seen in <FIG>), as illustrated in DETAIL A of <FIG>. The deployment thumbwheel may only be turned once the thumbwheel lock <NUM> (see <FIG>) has been set in the forward position, disengaging it from contact with the thumbwheel. Advancement of the hub <NUM> uncovers three slots <NUM> into which three commissure tabs <NUM> of the prosthetic mitral valve <NUM> (seen in <FIG>) will fit and be anchored. After anchoring of the commissure tabs <NUM> into the slots <NUM> by retraction of the hub <NUM> has been achieved, a third step in the loading of a prosthetic mitral valve <NUM> (seen in <FIG>) into the delivery apparatus <NUM> may be performed. The prosthetic mitral valve <NUM> (seen in <FIG>) can be crimped down to a minimum diameter by a loading mechanism (not shown), and then the sheath cannula <NUM> can be advanced forward so as to cover the valve, by rotation of the thumbwheel <NUM> in a counter-clockwise direction. The delivery apparatus <NUM> and prosthetic mitral valve <NUM> are then ready for deployment.

<FIG> illustrate another example of a delivery device for implanting a prosthetic valve in the heart transapically. However, one of skill in the art will appreciate that the delivery system may be modified and relative motion of the various components adjusted to allow the device to be used to deliver a prosthetic transseptally. The delivery apparatus is generally comprised of a handle <NUM> that is the combination of two halves (<NUM> and <NUM>), as well as a tip <NUM> that can smoothly penetrate the apex of the heart, and a flexible sheath <NUM> which is comprised of concentric catheters that are designed to translate axially and will be described in detail below.

The handle <NUM> includes a handle cap <NUM> which connects to a female threaded Luer adaptor <NUM> in order to provide a sealable exit for a <NUM>" diameter guide-wire (not shown). The handle cap <NUM> is attached to the handle <NUM> with threaded fasteners <NUM>. The female threaded Luer adaptor <NUM> is in threaded contact with the handle cap <NUM> through a tapped port, and when fully inserted squeezes against an O-ring (<NUM> best seen in <FIG>) which seals against the outer diameter of a guide-wire catheter (<NUM> best seen in <FIG>).

As can be seen in <FIG>, the handle <NUM> provides location for the control mechanisms used to position and deploy a prosthetic mitral valve. The handle <NUM> provides housing for a thumbwheel <NUM> that can be accessed through a window <NUM> that appears on both the top and bottom of the handle <NUM>. The thumbwheel <NUM> internally mates with a threaded insert (<NUM> in <FIG>) that actuates the sheath catheter <NUM>, and the mechanics of this interaction will be explained in detail below.

<FIG> also shows a first hemostasis tube <NUM> that is inserted internally through a slot <NUM>, and that mates with a first hemo-port through a hole (<NUM> and <NUM> in <FIG> respectively). The first hemostasis tube <NUM> allows for fluid purging between internal catheters. The position of the first hemostasis tube <NUM> along the slot <NUM> provides a visual cue as to the position of the sheath catheter <NUM>, and relative deployment phase of a prosthetic mitral valve (not shown). The relationship between the connection of the first hemostasis tube <NUM> and the sheath catheter <NUM> will be described below.

As can also be seen in <FIG>, a second hemostasis tube <NUM> is inserted into the handle <NUM> and mated to a second hemo-port (<NUM> in <FIG>) in order to allow fluid purging between internal catheters, and details of this insertion will be described below. Finally, a pin lock <NUM> provides a security measure against premature release of a prosthetic mitral valve, by acting as a physical barrier to translation between internal mechanisms. Pin lock prongs <NUM> rely on spring force to retain the pin lock <NUM> in the handle <NUM>, and a user must first pull out the pin lock <NUM> before final deployment of a prosthetic valve.

<FIG> also shows how the handle <NUM> is fastened together by use of threaded fasteners and nuts (<NUM> and <NUM> of <FIG> respectively), and countersunk locator holes <NUM> placed throughout the handle length.

Internal mechanisms of the delivery system are illustrated in detail in <FIG>, and the following descriptions will reveal the interactions between individual components, and the manner in which those components combine in order to create a system that is able to deliver a prosthetic mitral valve transapically or by other routes.

As seen in <FIG>, the flexible sheath <NUM> is comprised of four concentrically nested catheters. In order from smallest to largest in diameter, the concentrically nested catheters will be described in detail. The innermost catheter is a guide-wire catheter <NUM> that runs internally throughout the entire delivery system, beginning at the tip <NUM> and terminating in the female threaded Luer adaptor <NUM>. The guide-wire catheter <NUM> is composed of a lower durometer, single lumen Pebax extrusion and is stationary. It provides a channel through which a guidewire (not shown) can communicate with the delivery system. The next catheter is the hub catheter <NUM> which provides support for the hub <NUM> and is generally comprised of a higher durometer, single lumen PEEK extrusion. The hub catheter <NUM> is in mating connection with both the hub <NUM> at the distal end, and a stainless steel support rod <NUM> at the proximal end. The stainless steel support rod <NUM> is held fixed by virtue of a stopper <NUM> that is encased in the handle <NUM>. The hub catheter <NUM> is stationary, and provides support and axial rigidity to the concentrically nested catheters. The next catheter is the bell catheter <NUM>, which provides housing to the hub <NUM> and is generally comprised of a medium durometer, single lumen Pebax extrusion, including internal steel braiding and lubricious liner, as well as a radiopaque marker band (not shown). The bell catheter <NUM> translates axially, and can be advanced and retracted with respect to the hub <NUM>. The bell catheter <NUM> is in mating connection with the second hemo-port <NUM> at the proximal end, and hemostasis between the bell catheter <NUM> and the stainless steel support rod <NUM> can be achieved by purging the second hemostasis tube <NUM>. The bell catheter <NUM> is bumped up to a larger diameter <NUM> on the distal end in order to encapsulate the hub <NUM>. The outermost and final catheter is the sheath catheter <NUM> which provides housing for a prosthetic mitral valve (not shown), and which is able to penetrate the apex of the heart (not shown), by supporting and directing a tip <NUM> and assisting in the dilation of an incision in the heart wall muscle. The sheath catheter <NUM> is generally comprised of a medium durometer, single lumen Pebax extrusion, including internal steel braiding and lubricious liner, as well as radiopaque marker band (not shown). The sheath catheter <NUM> translates axially, and can be advanced and retracted with respect to the hub <NUM>. The sheath catheter <NUM> is in mating connection with the first hemo-port <NUM> at the proximal end, and hemostasis between the sheath catheter <NUM> and the bell catheter <NUM> can be achieved by purging the first hemostasis tube <NUM>.

As seen in <FIG>, the proximal end of the sheath catheter <NUM> is in mating contact with a first hemo-port <NUM>. The first hemo-port is in mating contact with a threaded insert <NUM>, and an O-ring <NUM>, which is entrapped between the first hemo-port <NUM> and the threaded insert <NUM> in order to compress against the bell catheter <NUM>, creating a hemostatic seal. As the thumbwheel <NUM> is rotated, the screw insert <NUM> will translate, and the sheath catheter <NUM> can be retracted or advanced by virtue of attachment. In order to provide adequate stiffness to dilate heart wall tissue, the distal edge of the sheath catheter <NUM> will abut against a shoulder <NUM> located on the tip <NUM>. This communication allows the tip <NUM> to remain secure and aligned with the sheath catheter <NUM> during delivery, and creates piercing stiffness.

<FIG> also details the mechanism through which the bell catheter <NUM> can be retracted or advanced with respect to the hub <NUM>. The thumbwheel <NUM> can be rotated to such an extent that the screw insert <NUM> will be brought into contact with two pins <NUM> that are press fit into the second hemo-port <NUM>. As the bell catheter <NUM> is in mating contact with the second hemo-port <NUM>, further rotation of the thumbwheel <NUM> will cause the second hemo-port <NUM> to translate and press against a spring <NUM> by virtue of connection to a second hemo-port cap <NUM>. This advancement will cause the bumped larger diameter section <NUM> of the bell catheter <NUM> to be retracted from the hub <NUM>. As the thumbwheel <NUM> is rotated in the opposite direction, restoring force produced by the spring <NUM> will cause the second hemo-port <NUM> to be pushed in the opposite direction, drawing the bumped larger diameter section <NUM> of the bell catheter <NUM> back over the hub <NUM>, an action that is necessary during the initial loading of a valve prosthesis.

<FIG> further details the manner in which hemostasis is achieved between the stainless steel support rod <NUM> and the bell catheter <NUM>. An O-ring <NUM> is compressed between the second hemo-port <NUM> and the second hemo-port cap <NUM>, creating a seal against the stainless steel support rod <NUM>. Hemostasis between the bell catheter <NUM> and the stainless steel support rod <NUM> can be achieved by purging the second hemostasis tube <NUM>, which is in communication with the void to be purged through a slot and hole <NUM>.

The deployment process and actions necessary to activate the mechanisms responsible for deployment are detailed in <FIG>. When performed in the reverse order, these actions also necessitate the first loading of a valve (not shown) prior to surgery.

As seen in <FIG>, manipulation of the thumbwheel <NUM> will provide translational control of the sheath catheter <NUM>. In order to effect the deployment of a heart valve (not shown), the user must withdraw the sheath catheter <NUM> from contact with the shoulder <NUM> of the tip <NUM> until it passes the larger diameter section <NUM> of the bell catheter <NUM>. A heart valve (not shown) will reside concentrically above the guide-wire catheter <NUM> in the position indicated by the leader for <NUM> in <FIG>, similarly as to the example illustrated in <FIG>. The sheath catheter <NUM> can be withdrawn until the screw insert <NUM> comes into contact with the pin lock <NUM>. The pin lock <NUM> must then be removed before further travel of the screw insert <NUM> can be achieved.

As seen in <FIG>, the pin lock <NUM> is removed from the handle <NUM> in order to allow further translation of the sheath catheter <NUM>. When the sheath catheter <NUM> is fully retracted, the larger diameter section <NUM> of the bell catheter <NUM> is also fully retracted, which completely frees the heart valve (not shown) from the delivery system. Three hub slots <NUM>, spaced circumferentially at about <NUM> degrees from each other provide the anchoring mechanism and physical link between delivery system and heart valve. Once the larger diameter section <NUM> of the bell catheter <NUM> has been withdrawn, the hub slots <NUM> become uncovered which allows the heart valve anchor (not shown) to fully expand.

<FIG> illustrates a distal portion of the delivery device in <FIG>. Three hub slots <NUM> are slidably disposed distally relative to the large diameter tip <NUM> of bell catheter <NUM>. These slots allow engagement with a prosthetic valve. The valve may be releasably held by the slots by disposing the commissure tabs or tabs <NUM> of the prosthetic valve into slots <NUM> and then retracting the slots <NUM> under tip <NUM> of bell catheter <NUM>. The prosthetic valve may be released from the delivery catheter by advancing the slots distally relative to the bell catheter so that the loading anchors or tabs <NUM> may self-expand out of and away from slots <NUM> when the constraint of tip <NUM> on bell catheter <NUM> has been removed.

<FIG> illustrates a prosthetic mitral valve <NUM> (as discussed above with reference to <FIG>) with the anchor tabs <NUM> disposed in the hub slots (not visible), and bell catheter <NUM> advanced thereover. Thus, even though most of the prosthetic valve <NUM> has self-expanded into its expanded configuration, the valve commissures remain in a collapsed configuration with the tabs <NUM> captured in slots <NUM>. Once the constraint provided by bell catheter <NUM> has been removed from the slots <NUM>, the tabs <NUM> may self-expand out of slots <NUM>, the commissures will open up to their unbiased position. The prosthetic valve is then disconnected and free from the delivery device.

<FIG> illustrate an example of a method of transapically delivering a prosthetic mitral valve. This example may use any of the prosthetic valves described herein, and may use any of the delivery devices described herein. <FIG> illustrates the general transapical pathway that is taken with entry into the heart at the apex <NUM>, through the left ventricle <NUM>, across the mitral valve <NUM> and into the left atrium <NUM>. The aortic valve <NUM> remains unaffected. Transapical delivery methods have been described in the patent and scientific literature, such as in International <CIT>, the entire contents of which are incorporated herein by reference.

In <FIG> a delivery device <NUM> is introduced through an incision in the apex <NUM> and over a guidewire GW through the ventricle <NUM>, past the mitral valve <NUM> with a distal portion of the delivery device <NUM> disposed in the atrium <NUM>. The delivery device has a rounded tip <NUM> that is configured to pass through and dilate the incision, and can be advanced through the heart without causing unwanted trauma to the mitral valve <NUM> or adjacent tissue. Suture <NUM> may be stitched around the delivery device <NUM> at the apex <NUM> using a purse string stitch or other patterns known in the art in order to prevent excessive bleeding and to help hold the delivery device in position.

In <FIG>, the outer sheath 2214a of the delivery device <NUM> is retracted proximally relative to the prosthetic mitral valve <NUM> (or the prosthetic mitral valve is advanced distally relative to the outer sheath 2214a) to expose the alignment element <NUM> and a portion of the atrial skirt region <NUM> on the prosthetic mitral valve <NUM> which allows the atrial skirt region <NUM> to begin to partially radially expand outward and flare open. Alignment element <NUM> may include a pair of radiopaque markers 2218a which facilitate visualization under fluoroscopy. The physician can then align the alignment element so that the radiopaque markers 2218a are disposed on either side of the anterior mitral valve leaflet. Delivery device <NUM> may be rotated in order to help align the alignment element. The alignment element may be situated adjacent the aortic root and between the fibrous trigones of the native anterior leaflet.

In <FIG> once alignment has been obtained, the sheath 2214a is further retracted proximally, allowing radial expansion of the atrial skirt <NUM> which flares outward to form a flange. Proximal retraction of the delivery device <NUM> and prosthetic valve <NUM> seat the atrial skirt <NUM> against an atrial surface adjacent the mitral valve <NUM> thereby anchoring the prosthetic valve in a first position.

<FIG> shows that further proximal retraction of sheath 2214a exposes and axially removes additional constraint from the prosthetic valve <NUM>, thereby allowing more of the valve to self-expand. The annular region <NUM> expands into engagement with the mitral valve annulus and the ventricular trigonal tabs <NUM> and the posterior tab <NUM> radially expand. Portions of the ventricular skirt serve as deployment control regions and prevent the entire ventricular skirt from expanding because they are still constrained. The tabs are captured between the anterior and posterior mitral valve leaflets and the ventricular wall. The posterior ventricular anchoring tab <NUM> may be aligned in the middle of the posterior mitral valve leaflet where there is an absence of chordae attachments, and is passed over the posterior leaflet to seat between the posterior leaflet and the ventricular wall. The two ventricular trigonal anchoring tabs <NUM> are positioned on either side of the anterior leaflet with their heads positioned at the fibrous trigones. Slight rotation and realignment of the prosthesis can occur at this time. As the prosthesis expands, the anterior trigonal tabs anchor against the fibrous trigones, capturing the native anterior leaflet and chordae between the tabs and the anterior surface of the prosthetic valve, and the posterior ventricular tab anchors between the ventricular wall and the posterior leaflet, capturing the posterior leaflet between the posterior anchoring tab and the posterior surface of the prosthetic valve assembly.

<FIG> shows that further retraction of sheath 2214a releases the ventricular trigonal tabs and the posterior tab and the deployment control regions of the ventricular skirt <NUM> are also released and allowed to radially expand outward against the native mitral valve leaflets. This creates a sealing funnel within the native leaflets and helps direct blood flow through the prosthetic mitral valve. With the commissures of the prosthesis still captured within the delivery system, very minor adjustments may still be made to ensure accurate positioning, anchoring and sealing. The prosthetic valve is now anchored in four positions. The anchor tabs <NUM> are then released from the delivery device by retraction of an inner shaft, allowing the tabs to self-expand out of slots on the delivery catheter as previously discussed above and shown in <FIG>. The prosthetic valve is now implanted in the patient's heart and takes over the native mitral valve. The delivery device <NUM> may then be removed from the heart by proximally retracting it and removing it from the apex incision. The suture <NUM> may then be tied off, sealing the puncture site.

<FIG> illustrate an example of transseptally delivering a prosthetic mitral valve. This example may use any of the prosthetic valves described herein, and may use any of the delivery devices described herein if modified appropriately. One of skill in the art will appreciate that relative motion of the various shafts in the delivery system examples disclosed above may need to be reversed in order to accommodate a transseptal approach. <FIG> illustrates the general transseptal pathway that is taken with the delivery device passing up the vena cava <NUM> into the right atrium <NUM>. A transseptal puncture <NUM> is created through the atrial septum, often through the foramen ovale, so that the device may be passed into the left atrium <NUM>, above the mitral valve <NUM> and adjacent the left ventricle <NUM>. Transseptal techniques have been published in the patent and scientific literature, such as in <CIT>, the entire contents of which are incorporated herein by reference.

In <FIG> a delivery device <NUM> is passed over a guidewire GW through the vena cava <NUM> into the right atrium <NUM>. The delivery device <NUM> is then transseptally passed through the atrial wall into the left atrium <NUM> adjacent the mitral valve <NUM>. The guide-wire GW may be disposed across the mitral valve <NUM> in the left ventricle <NUM>. The distal tip of the delivery device typically includes a nose cone or other atraumatic tip to prevent damaging the mitral valve or adjacent tissue.

In <FIG>, the outer sheath 2214a of the delivery device <NUM> is retracted proximally relative to the prosthetic mitral valve <NUM>. Alternatively, a distal portion 2314b of the delivery device <NUM> may be advanced distally relative to the prosthetic valve <NUM> to expose the alignment element <NUM> and a portion of the atrial skirt region <NUM> on the prosthetic mitral valve <NUM> which allows the atrial skirt region <NUM> to begin to partially radially expand outward and flare open. Alignment element <NUM> may include a pair of radiopaque markers 2316a which facilitate visualization under fluoroscopy. The physician can then align the alignment element so that the radiopaque markers 2316a are disposed on either side of the anterior mitral valve leaflet. The alignment element may be situated adjacent the aortic root and between the fibrous trigones of the native anterior leaflet. Delivery device <NUM> may be rotated in order to help align the alignment element.

In <FIG> once alignment has been obtained, the distal portion 2314b is further advanced distally allowing radial expansion of the atrial skirt <NUM> which flares outward to form a flange. Distally advancing the delivery device <NUM> and prosthetic valve <NUM> seats the atrial skirt <NUM> against an atrial surface adjacent the mitral valve <NUM> thereby anchoring the prosthetic valve in a first position.

<FIG> shows that further distal advancement of distal portion 2314b exposes and axially removes additional constraint from the prosthetic valve <NUM>, thereby allowing more of the valve to self-expand. The annular region <NUM> expands into engagement with the mitral valve annulus and the ventricular trigonal tabs <NUM> and the posterior tab <NUM> radially expand. Portions of the ventricular skirt serve as deployment control regions since they remain constrained and thus the entire ventricular skirt cannot expand. The tabs are captured between the anterior and posterior mitral valve leaflets and the ventricular wall. The posterior ventricular anchoring tab <NUM> may be aligned in the middle of the posterior mitral valve leaflet where there is an absence of chordae attachments, and is passed over the posterior leaflet to seat between the posterior leaflet and the ventricular wall. The two ventricular trigonal anchoring tabs <NUM> are positioned on either side of the anterior leaflet with their heads positioned at the fibrous trigones. Slight rotation and realignment of the prosthesis can occur at this time. As the prosthesis expands, the anterior trigonal tabs anchor against the fibrous trigones, capturing the native anterior leaflet and chordae between the tabs and the anterior surface of the prosthetic valve, and the posterior ventricular tab anchors between the ventricular wall and the posterior leaflet, capturing the posterior leaflet between the posterior anchoring tab and the posterior surface of the prosthetic valve assembly.

<FIG> shows that further distal advancement of distal portion 2314b releases the ventricular trigonal tabs and the posterior tab and the ventricular skirt <NUM> is also released and allowed to radially expand outward against the native mitral valve leaflets without engaging the ventricular wall. This creates a sealing funnel within the native leaflets and helps funnel blood flow through the prosthetic valve. With the commissures of the prosthetic valve still captured by the delivery system, very minor adjustments may still be made to ensure accurate positioning, anchoring and sealing. The prosthetic valve is now anchored in four positions. The anchor tabs <NUM> are then released from the delivery device by further advancement of an inner shaft, allowing the tabs to self-expand out of slots on the delivery catheter as previously discussed above and shown in <FIG>. The prosthetic valve is now implanted in the patient's heart and takes over the native mitral valve. The delivery device <NUM> may then be removed from the heart by proximally retracting it back through the atrial septum, and out of the vena cava.

<FIG> shows the prosthetic valve <NUM> anchored in the mitral space after transapical or transseptal delivery. Prosthetic valve <NUM> may be the prosthetic mitral valve illustrated in <FIG> or any of the other prosthetic valves disclosed herein, and delivered by methods shown in <FIG>- ventricular skirt <NUM> is also radially expanded outward to engage and press outwardly <NUM> or <FIG>. The prosthetic valve <NUM> has radially self-expanded into engagement with the mitral valve to anchor it in position without obstructing other portions of the heart including the left ventricular outflow tract such as aortic valve <NUM>. The anterior trigonal tabs <NUM> (only <NUM> seen in this view) and the posterior ventricular tab <NUM> are radially expanded outward from the rest of the ventricular skirt <NUM> and the anterior leaflet <NUM> and posterior leaflet <NUM> are captured between the respective tab and the ventricular skirt <NUM> to form an anchor point. The at least some of the chordae tendineae and papillary muscles but may not press against the ventricular wall. The annular region <NUM> is expanded radially outward to engage and press against the mitral valve annulus, and the atrial skirt <NUM> has also expanded outwardly to form a flange that rests on top of the mitral valve against the atrium. Thus, the prosthetic valve <NUM> is anchored in four positions in the mitral space which prevents the prosthetic valve from migrating or dislodging during contraction of the heart. Moreover, using four anchor points lessens the anchoring pressure that is required to be applied in any given anchoring zone as compared to a prosthesis that is anchored in only a single anchoring zone, or in any combination of these four anchoring zones. The consequent reduction in radial force required to be exerted against the native structures in each zone minimizes the risk of obstruction or impingement of the nearby aortic valve or aortic root caused by the displacement of the native mitral valve apparatus. Valve leaflets <NUM> form a tricuspid valve which opens with antegrade blood flow and closes with retrograde blood flow. Tab <NUM> on a tip of the commissures <NUM> (best seen in <FIG>) remains free after disengagement from the delivery device.

<FIG> illustrates the prosthetic valve <NUM> of <FIG> anchored in the mitral space and viewed from the left ventricle, looking upward toward the atrium. As previously mentioned, the prosthetic valve <NUM> may be transapically or transseptally delivered and may be the prosthetic mitral valve illustrated in <FIG>, delivered by methods shown in <FIG> or <FIG>. This view more clearly illustrates anchoring and engagement of the prosthetic mitral valve <NUM> with the adjacent tissue. For example, the three valve leaflets <NUM> forming the tricuspid valve are shown in the open position, allowing blood flow therepast. Additionally, the anterior trigonal tabs <NUM> and the posterior ventricular tab <NUM> are shown radially expanded outward into engagement with the ventricular heart tissue <NUM>. The anterior portion of the prosthetic valve in between anterior trigonal tabs <NUM> is approximately flat to match the corresponding flat anatomy as previously discussed above. The flat shape of the anterior portion of the prosthetic valve prevents the prosthetic valve from impinging on and obstructing adjacent anatomy such as the left ventricular outflow tract including the aortic valve. <FIG> also illustrates how the ventricular skirt <NUM> expands radially outward against the native mitral valve leaflets.

Any of the prosthetic valves may also be used as a drug delivery device for localized drug elution. The therapeutic agent may be a coated on the prosthetic valve, on the tissue covering the anchor, on both, or otherwise carried by the prosthetic valve and controllably eluted therefrom after implantation. Examples of drugs include anti-calcification drugs, antibiotics, anti-platelet aggregation drugs, anti-inflammatory drugs, drugs which inhibit tissue rejection, anti-restenosis drugs, anti-thrombogenic drugs, thrombolytic drugs, etc. Drugs which have these therapeutic effects are well known to those of skill in the art.

Any example of a prosthetic valve disclosed herein may include one or more anterior anchor tabs and/or one or more posterior anchor tabs, or anchor tabs may be positioned elsewhere on the expandable frame (e.g. laterally or medially). While these examples are promising, in certain situations, it can be challenging to observe the anchor tabs under fluoroscopy or echocardiography. Moreover, under certain circumstances, the tips of the anchor tabs may engage and irritate the tissue against which the tab anchors or cause trauma. Therefore, improved anchor tabs may be desirable in overcoming at least some of these challenges.

In any of the examples of prosthetic valves with anchor tabs, it may be desirable to modify the anchor tabs so that they are more easily observed under fluoroscopy, echocardiography or other visualization techniques used in a catheterization laboratory or during any medical procedure including visits to a physician. <FIG> shows a prosthetic valve <NUM> with an anchor tab <NUM> on the ventricular end (the prosthesis is inverted with the atrial flange on the lower end). The prosthetic valve <NUM> may be any of the prosthetic valves disclosed herein and the anchor tab <NUM> may be an anterior anchor tab, a posterior anchor tab, or any of the anchor tabs disclosed herein. <FIG> illustrate some examples of anchor tabs <NUM> that may be used with any anchor tab of any prosthesis disclosed herein. The anchor tabs may be formed from struts that are covered with a covering such as Dacron, or the anchor tabs may be solid.

<FIG> shows anchor tab <NUM> with a base <NUM> and the free end <NUM>. The base is coupled to the prosthetic valve and may be coupled to the ventricular skirt. The base has a narrow elongate section with a rounded end that is coupled to the prosthetic valve. The free end <NUM> is the end that engages and anchors against tissue, for example against a fibrous trigone if the anchor is an anterior anchor, or against a posterior portion of the annulus if the anchor is a posterior anchor. The free end has an enlarged head region relative to the base and the enlarged head portion provides greater contact surface area therefore distributing forces over a larger surface area thereby reducing the potential of tissue trauma, as well as providing a more radiopaque or echogenic area for visualization. Optionally, the free end may include a plurality of slots that extend partially or entirely through the tab to provide a pattern that also may facilitate visualization under radiography or ultrasound. Here, the optional pattern includes two unconnected slots on either side of the free end that form a chevron, and two horizontal slots adjacent the engagement edge of the free end. One of the horizontal slots is longer than the other horizontal slot. Again, this optional pattern may help with visualization.

Additionally, having slots in the anchor tab will allow the anchor tab to have desirable mechanical properties, such as a tip flexibility or stiffness, thereby further avoiding tissue trauma. The slots may be replaced with radiopaque or echogenic filaments or other materials that enhance visibility.

<FIG> illustrates another example of an anchor tab that may be used with any anchor tab on any prosthetic valve disclosed herein. Here the tab <NUM> generally takes the same form as the tab in <FIG> with the major difference being that there are no slots and this example includes a cover or coating. The tab <NUM> includes a base <NUM> and also a free end <NUM> that are substantially the same as the free end in <FIG>. However, here the free end <NUM> does not include the slots of <FIG>. Also, the free end includes a cover or coating <NUM> that is disposed over or otherwise coupled to the free end <NUM>. The cover or coating may be any material that increases visualization under x-rays or ultrasound. For example, the coating or cover may include silicone to promote echogenicity, or a dense material to promote radiopacity. In addition to facilitating visualization, the cover or coating also provides a cushion and/or larger surface area to distribute forces thereby minimizing or preventing trauma to tissue when the tab is anchored against tissue and hence the cover or coating may be used to control the mechanical properties of the anchor tab.

<FIG> illustrates another example of an anchor tab <NUM> which generally takes the same form as the tab in <FIG> with the major difference being the use of surface features. Tab <NUM> includes a base <NUM> and a free end <NUM> that generally take the same form as the base and free end in <FIG>. In this example, the anchor tab is formed from a plurality of interconnected struts <NUM> and a covering is disposed over the struts. The covering may be any material such as Dacron, ePTFE, Teflon, tissue, etc. The individual struts <NUM> may have surface features or be etched to have surface features <NUM> to enhance radiopacity or echogenicity. The surface features may also enhance the mechanical properties. Some or all of the struts may have the surface features or etching.

<FIG> shows another example of an anchor tab with features that may be used to enhance visualization or the mechanical properties of the tab. Tab <NUM> generally takes the same form as the tab in <FIG> and has a base <NUM> and free end <NUM> substantially similar to those described in <FIG>. The anchor tab may have one or more apertures extending through the anchor tab. Here, the anchor tab includes an aperture <NUM> in the free end, and two apertures <NUM>, <NUM> in the base. Aperture <NUM> is the larger aperture and may be a circular hole or another pattern, while the two base apertures <NUM>, <NUM> also are circular and both smaller than the free end aperture <NUM> but one aperture closest to the edge of the base being larger than the other aperture in the base. An operator is able to see the apertures and determine the position of the free end and the base end. The apertures also may be adjusted to increase or decrease flexibility or other mechanical properties of the anchor tabs as desired.

<FIG> illustrate additional examples of anchor tabs that may be used with any of the prosthetic valves disclosed herein.

<FIG> shows an anchor tab having a base <NUM> and a free end <NUM> similar to those previously described in <FIG> above. The free end includes a plurality of round holes <NUM> disposed around the perimeter of the free end with an axially oriented racetrack shaped slot <NUM> parallel with the longitudinal axis of the anchor tab in the free end region. A linear array of round holes <NUM> is disposed in between the base and free end, and a wide hole <NUM> is disposed on the base. The wide hole <NUM> allows tethers or other objects to be coupled to the base of the anchor tab (also sometimes referred to as an elbow) to control elbow deployment. Round holes <NUM> are disposed on either side of the wide hole <NUM>. Again, the holes help facilitate visualization of the anchor tab and provide desirable mechanical properties to the anchor tab. The holes may also be used to pass suture through in order to secure objects (e.g. a cover) to the anchor tab.

<FIG> is similar to the example of <FIG> with a different pattern of slots and holes. The base <NUM> includes a wide hole <NUM> through which a tether or other control element may be disposed or coupled to in order to control elbow deployment. Either side of wide hole <NUM> includes a linear array of holes <NUM> to mark the base with an arcuate slot <NUM> under the wide hole <NUM>. The middle portion of the anchor tab between the base and free end includes a linear array of holes <NUM> with horizontal linear slots <NUM>, <NUM> of varying length extending down into the free end with round and oval holes <NUM> disposed between some of the horizontal slots. A vertical oval slot maybe disposed in between horizontal slots. A final linear array of round holes <NUM> may be horizontally oriented along the free end.

<FIG> illustrates another example of hole and slot patterns which may be used in an anchor tab to control radiopacity or echogenicity as well as mechanical characteristics of the anchor tab. The hole pattern is substantially the same as in <FIG> with a few modifications. For example, the arcuate slot <NUM> has been replaced with a chevron shaped slot <NUM> pointing toward the base, and the horizontal slots <NUM>, <NUM> have been replaced with linear slots that form chevrons pointing toward the free end. The chevrons may be open <NUM> or closed <NUM> in the region between the base <NUM> to the free end <NUM>.

<FIG> shows another hole and slot pattern that may be used in any anchor tab. The anchor tab includes a base <NUM> and a free end <NUM>. The hole pattern near the base is similar to that of <FIG> except without chevron <NUM>. Closed chevrons <NUM> pointing toward the free end extend from the mid-section of the anchor toward the free end, and a plurality of round holes extend along the perimeter of the free end similar to <FIG>. Other aspects of the hole pattern are similar to <FIG>.

<FIG> illustrates still another hole and slot pattern that may be used in an anchor tab. Here, the base <NUM> includes an open slot <NUM> that allows a tether, filament or other object to be easily coupled or decoupled from the aperture in the base and round holes <NUM> surround the slot and aperture. A linear array of holes <NUM> extends vertically down the tab in the middle section between the base and the free end. A vertically oriented oval slot <NUM> marks a central region of the free end and the perimeter of the free end <NUM> is outlined with a plurality of round holes <NUM>.

The examples in <FIG> are not intended to be limiting and are disclosed only to illustrate how slots, holes and other surface features may be incorporated into the anchor tabs in order to facilitate visualization and control mechanical properties of the anchor tab.

<FIG> illustrate another example of an anchor tab that will be more visible as well as providing reduced contact pressure and therefore a less traumatic anchor. This anchor tab may be used as an anterior anchor tab, a posterior anchor tab, or any anchor tab in any of the prosthetic valve examples disclosed herein.

<FIG> illustrates a prosthetic valve <NUM> in a collapsed configuration and constrained by an outer tubular element <NUM> such as a sheath or catheter shaft and this facilitates delivery to the treatment region in the collapsed configuration. The prosthetic valve <NUM> may be any of the prosthetic valves disclosed herein and includes anchor tabs <NUM> which may be anterior anchor tabs, posterior anchor tabs, combinations thereof, or other anchor tabs. In this example, only two anchor tabs are seen, but a third anchor tab is hidden and therefore this example includes two anterior anchor tabs and one posterior anchor tab. The prosthetic valve also includes commissure post <NUM> with an enlarged head for releasably coupling with a delivery catheter as previously disclosed above. The anchor tabs <NUM> are also constrained by sheath <NUM> in a collapsed configuration such that the anchor tabs are disposed in a substantially linear shape that extends substantially parallel with the longitudinal axis of the prosthetic valve.

In <FIG>, the sheath <NUM> is retracted away from the prosthesis <NUM> as indicated by the arrow such that the atrial portion of the prosthetic valve self-expands to form an atrial skirt or flange <NUM> as previously described. As the sheath <NUM> is further retracted, the anchor tabs <NUM> become unconstrained and they self-expand substantially the same way as the other anchor tabs described earlier in this specification. However, the free ends of the anchor tabs are also biased to roll up into coils <NUM>. The coiled ends may form a flat spiral spring (sometimes also referred to as a clock spring). Once the sheath is fully retracted (not illustrated in <FIG>), the remainder of the prosthesis self-expands and the commissures are released from the catheter.

<FIG> shows the prosthesis fully expanded and released from the delivery catheter. The prosthesis in the fully expanded configuration takes substantially the same form as the expanded configurations of other valve prostheses described herein. The major difference being the coiled tips <NUM> of the anchor tabs. Because there is more material in the coiled tips, mass and/or density is also increased and the tips will be more visible under x-ray or ultrasound. Additionally, because the engagement portion of the anchor tab is smooth and curved as well as having a larger surface area, trauma to tissue will also be minimized or avoided.

The prosthetic valve may be formed from any number of self-expanding or shape memory materials such as Nitinol, resilient polymers or other materials known in the art. The prosthetic valve may also be formed from balloon expandable materials and a balloon catheter may be used to expand the prosthesis.

The coiled anchor tab may also be combined with any of the covering, coating, slotted, textured, or otherwise modified anchor tabs disclosed herein.

As discussed previously, the prosthetic valve may be self-expanding, balloon expandable or it may be expandable by other techniques known in the art. In certain circumstances such as during self-expansion, the prosthesis can spring open abruptly causing the prosthesis to move or jump from its targeted deployment location. Therefore, it may be desirable to provide additional deployment control mechanisms to the prosthesis in order to ensure more accurate deployment and anchoring at the target treatment site.

A cinching or lasso mechanism may be coupled to any portion of the prosthetic valve in order to control radial expansion. For example, the lasso may be coupled to the atrial flange, the annular region, the anchor tabs, or the lasso may extend circumferentially around the ventricular portion of the prosthetic valve.

For example, <FIG> show a lasso coupled to the perimeter of the atrial flange in the expanded and collapsed configurations, respectively.

<FIG> shows the prosthetic valve in a partially expanded configuration. The prosthetic valve may be any of the prosthetic valves disclosed herein, and the atrial flange is in the expanded configuration while the remainder of the prosthetic valve is housed in a collapsed configuration in a distal capsule <NUM> coupled to an elongate shaft <NUM> in the delivery system. The loop portion <NUM> of the lasso extends circumferentially around the perimeter of the flange and the free ends <NUM> of the lasso extend proximally away from the prosthetic valve. The free ends <NUM> of the lasso maybe extend proximally, and run substantially parallel to the longitudinal axis of the delivery system. The free ends may be slidably disposed in a lumen of another shaft <NUM> that is part of the delivery system, or the free ends may run along an outer surface or in a lumen or annular space of the delivery catheter in order to prevent entanglement. Shaft <NUM> may be disposed inside a lumen or annular space of the delivery catheter, or shaft <NUM> may run alongside an outer surface of the delivery catheter. The free ends extend proximally to the proximal end of the delivery catheter where they may be manually controlled by an operator, or the free ends may be coupled to an actuator that allows the operator to manipulate the lasso. Appling tension to the lasso will generally tighten the lasso and therefore collapse the atrial flange while releasing tension will relax the lasso thereby allowing the atrial flange to expand. Collapsing the atrial flange allows the prosthetic valve to be recaptured and re-sheathed in a capsule or lumen of the delivery catheter and repositioned or removed from the patient.

The lasso may be formed from any filament such as a flexible wire or a suture. The lasso (whether a suture, wire, or other component) is passed through eyelets <NUM> which are disposed around the perimeter of the atrial flange, or the lasso may be disposed through other connector features which are disposed on the prosthetic valve frame. The eyelets <NUM> may be fabric tabs which are folded over themselves to form a channel through which the filament passes and then the ends of the tabs are coupled to the struts <NUM> of the prosthetic valve (e.g. by suturing) or coupled to the cover <NUM> (e.g. Dacron cover) disposed over the prosthetic valve.

Once the prosthetic valve has been deployed in a desired location correctly, the free ends of the lasso may be released at the proximal end and one end of the filament pulled until the lasso is pulled out of the eyelets and released from the atrial flange thereby removing the lasso completely from the prosthetic valve.

<FIG> shows the prosthetic valve of <FIG> when tension is applied to the lasso, thereby collapsing the atrial flange on the prosthetic valve so that it may be re-sheathed and then either repositioned and redeployed or removed from the patient.

In some examples, the lasso may be fixedly attached the prosthetic valve such that at least a portion of the lasso remains with the prosthetic valve after implantation.

<FIG> illustrates another example of a lasso <NUM> that is fixedly attached to the prosthetic valve <NUM> which may be any of the prosthetic valves disclosed herein. Here, the lasso <NUM> is attached to the perimeter of the atrial flange of the prosthetic valve. The lasso is formed from a single filament such as a wire or suture that forms a closed loop around the atrial flange. In other examples, more than one filament may be used to form the filament. One or more (here there are two) connectors <NUM> such as loops are formed in the filament and extend outward and away from the lasso and provide an eyelet that may be releasably coupled to an actuation element such as a catheter shaft or tether. The lasso is fixed to the prosthetic valve by passing the filament through tabs <NUM>, <NUM> coupled to the struts <NUM> of the prosthetic valve or coupled to the covering <NUM> (e.g. a Dacron cover) disposed over the struts <NUM> of the prosthetic valve frame. The tabs may include short tabs <NUM>, or long tabs <NUM>. The long tabs <NUM> may include a slot or open window portion <NUM> to allow the connectors <NUM> to extend through the slot or window to provide access to the looped portion of the connector. The looped portion of the connector may be formed by bunching a portion of the filament together and knotting it or crimping it with a crimping ring to form the loop which can act as an eyelet.

The lasso of <FIG> may be tensioned to collapse the atrial flange or tension may be reduced in order to permit the atrial flange to self-expand. Again, this allows controlled expansion of the atrial flange, or if desired the atrial flange may be collapsed, re-sheathed and repositioned or removed from the patient.

<FIG> illustrate the prosthetic valve of <FIG> in different configurations. <FIG> shows the prosthetic valve <NUM> with tension applied to the lasso <NUM> thereby collapsing the atrial flange into the collapsed configuration. The ventricular portion of the prosthetic valve is also in a collapsed configuration and housed in a capsule <NUM>. Tabs <NUM> hold the lasso to the prosthetic valve <NUM> as previously described. Two tethers <NUM> are releasably coupled to the loops <NUM> formed in the lasso (best seen in <FIG>). The tethers may be filaments such as wire or suture, and the tethers extend proximally substantially parallel to the longitudinal axis of the delivery catheter shaft <NUM> which carries the prosthetic valve. The tethers may be housed in a lumen of another catheter shaft <NUM> to prevent entanglement and control friction, or the tethers may simply run alongside the delivery catheter or in a lumen or annular space of the delivery catheter. The proximal ends of the tethers may be manually controlled by an operator or coupled to an actuator on a handle which can be actuated by an operator, thereby controlling the tension in the tethers and therefore controlling the expanded or collapsed configuration of the atrial flange.

<FIG> shows tension relaxed in the tethers <NUM> thereby allowing the atrial flange to expand while the ventricular portion of the prosthetic valve remains collapsed or partially collapsed in the capsule <NUM>. If the operator needs to reposition the prosthetic valve or remove it from the patient, tension may be re-applied to the tethers to collapse the atrial flange so that it can be re-sheathed and repositioned or removed.

<FIG> shows the atrial flange fully expanded and once deployed correctly, the operator may remove all tension from the tethers <NUM> and connectors <NUM> are released from the loops <NUM> in the lasso thereby decoupling the tethers from the lasso. The tethers <NUM> and their protective sheaths <NUM> may then be removed from the patient while the lasso <NUM> remains attached to the prosthetic valve and implanted in the patient. The connectors may be any connector element which allows releasable coupling of the tethers with the loops, such as any of those described below.

<FIG> illustrate a similar lasso deployment control mechanism as in <FIG> above, with the main difference being the tether control mechanism <NUM> included. Other aspects of <FIG> are substantially the same as in <FIG>.

In <FIG>, tethers <NUM>, here three tethers, enter channels <NUM> in a tether control element <NUM> in a direction that is substantially parallel to the longitudinal axis of the delivery catheter <NUM>. The channels <NUM> are formed so that the tethers exit the tether control element <NUM> in a direction that is transverse or orthogonal to the longitudinal axis of the delivery catheter <NUM>. This helps prevent entanglement of the tethers and also directs tensile forces delivered to the lasso by the tethers to more radially inwardly directed to the lasso which will facilitate collapse of the lasso and atrial flange when tension is applied, as seen in <FIG>. The tether control element may have proximal and distal facing surfaces which are beveled to ensure that the tension control element does not get caught on any adjacent surfaces or cause any trauma to adjacent tissue which it may contact. Other aspects of <FIG> are substantially the same as <FIG>.

In <FIG>, the tension is released from the tethers, releasing the lasso and allowing the atrial flange to expand. Other aspects of <FIG> are generally the same as in <FIG>.

<FIG> shows the tethers <NUM> released from the connector loops <NUM> on the lasso. The tethers and connector element may then be removed from the patient. Other aspects of <FIG> are generally the same as in <FIG>.

<FIG> illustrate another example of a mechanism that may be used to control actuation of a lasso such as in <FIG>. <FIG> are generally the same as discussed with respect to <FIG> with the major difference being the coupling/uncoupling of the tethers to the loops in the lasso.

<FIG> shows the prosthetic valve <NUM> which may be any of the valves disclosed herein, in a collapsed configuration with the ventricular portion disposed in a capsule <NUM>. A lasso <NUM> passed around the perimeter of the atrial flange through tabs or eyelets <NUM> coupled to the expandable frame or a cover over the frame, is tensioned to hold the atrial flange in a collapsed configuration. The loops <NUM> connected to the tether extend through the tether control element <NUM> so that the loops are superior to the tether control element <NUM>. The tether control element helps prevent entanglement of the various shafts and filaments as well as helping to direct forces provided by the tether as previously discussed above. A tether <NUM> having a looped end is coupled to the lasso tether <NUM> by disposing the tether <NUM> loop under the loop <NUM> of the lasso and a filament such as a wire <NUM> is then passed through both loops. Thus, when tension is applied to the tether <NUM>, the loops remain interlocked because of the filament <NUM> and the lasso may be tightened to collapse the atrial flange. The filament <NUM> may extend alongside the delivery catheter or may be disposed in a lumen in a shaft or sheath (not illustrated). The tether <NUM> and/or the shaft or sheath may run alongside the delivery catheter or be housed in a lumen or annular space of the delivery catheter.

When the operator desires to release tension in the lasso, tension may be released in the tether <NUM> while it is still coupled to the lasso loop <NUM> (the filament is still disposed in both tether loop and lasso loop). This allows the atrial flange to self-expand as seen in <FIG>. If the operator desires, tension may be re-applied and the atrial flange collapsed and then the valve may be repositioned and redeployed or removed from the patient.

<FIG> shows that once the prosthetic valve is correctly positioned and the atrial flange is expanded, the filament <NUM> may be retracted proximally and removed from the loops <NUM>, <NUM> decoupling the loops from one another. The loop <NUM> on the lasso is coupled to the prosthetic valve and therefore remains implanted in the patient while the filament <NUM> and tether <NUM> are removed from the patient.

In any of the tether examples, the tethers coupled to the lasso may be disposed in a lumen of a shaft or sheath, or the tether may remain disposed free of any lumen and extend toward a proximal end of the delivery catheter. Any tether may only be a short segment of a tether that may also be joined to a catheter shaft that initiates the pulling action and controls tension and thus the actual tether segment does not have to extend all the way back to the proximal end of the delivery catheter.

<FIG> illustrate examples of connectors which may be used to releasably couple a tether with any of the lasso examples disclosed above, such as in <FIG>. <FIG> shows a tether <NUM> slidably disposed in a lumen of an outer shaft <NUM> with a connector <NUM> at the distal free end of the tether as previously described in <FIG>. The connector <NUM> is a partially cylindrically shaped element with a shoulder region <NUM> that extends radially outward from the tether to provide a region on which the loop <NUM> of the lasso may rest without falling off and a grooved region <NUM> extending along the longitudinal axis of the cylinder provides a channel in which both ends of tether <NUM> may lie after looping around the shoulder region. When tension is applied to the loop, the loop will remain coupled to the connector. When tension is removed, the loop may be uncoupled from the connector element releasing the lasso from the tethers. The tension may be adjusted to vary the hoop stress applied to the lasso and this controls the speed of expansion or contraction, or the size of the atrial flange. The outer shaft <NUM> may lie alongside the delivery catheter (not illustrated) or it may be disposed in a lumen or an annular region of the delivery catheter (also not illustrated).

<FIG> shows another example of a connector which may be used to releasably coupled the tether to the loops of a lasso. This example is similar to the example in <FIG> with the major difference being the connector <NUM>. Again, a tether <NUM> is slidably disposed in a lumen of an outer catheter or shaft <NUM>. A connector <NUM> is attached to the free end (distal end) of tether <NUM>. The connector is a rectangular block and therefore has a wide shoulder region on which the looped portion <NUM> may lie when wrapped therearound and the opposite ends of the loop <NUM> also lie flat against one side of the rectangular block connector. Other aspects of this example of connector a generally the same as previously described with respect to <FIG>.

<FIG> shows another example of a connector which may be used to releasably couple the tether to the lasso. In this example, the tether <NUM> is a filament of wire or suture that passes through a lumen of outer shaft <NUM>. The tether <NUM> then forms a loop <NUM> and wraps around a ball connector <NUM> that is attached to the lasso <NUM>. When tension is applied to tether <NUM>, the ball connector <NUM> is pulled toward the distal end of the outer shaft <NUM> preventing the loop <NUM> in the tether from uncoupling from the ball, holding the lasso in a tensioned configuration. When tension on the tether <NUM> is released, the loop <NUM> maybe released from the ball connector <NUM> releasing tension on the lasso <NUM> and thereby allowing the atrial flange to open. Other aspects of this example of connector are generally the same as previously described in <FIG>.

In another example (not illustrated), the ball may be coupled to the tether <NUM> and the loops <NUM> (best seen in <FIG>) may be releasably coupled to the ball.

The lasso in these examples was applied to the atrial flange of the prosthetic valve. This is not intended to be limiting. The lasso may be applied to any one or more regions of the prosthetic valve to control expansion or collapse of one or more regions of the prosthetic valve. For example, a lasso may be applied to a ventricular portion of the prosthetic valve and the anchor tabs to control the radial distance between the free end of the anchor tab and the outer surface of the ventricular skirt of the prosthesis (sometimes also referred to as the tab elbow distance). This distance may be adjusted as a part of the manufacturing process, prior to delivery or after delivery to control tab contact with the adjacent tissue. Or the lasso may be applied to the ventricular skirt, or the annular region, or combinations of two or more regions of the prosthetic valve.

<FIG> illustrate another example of deployment control mechanism used control expansion of a prosthetic valve which may be any of the prosthetic valves disclosed herein, and any of which may be used as a prosthetic mitral valve.

In <FIG>, a prosthetic valve <NUM> is in the collapsed configuration. The ventricular portion is collapsed and housed in a capsule <NUM>. The atrial portion <NUM> is constrained and held in a collapsed configuration by a ribbon or straitjacket <NUM> that is wrapped therearound. The straitjacket <NUM> is an elongate ribbon that may have a length longer than the width such that the ratio of length to width is greater than one. A tab <NUM> is formed in one end of the ribbon and a slot <NUM> is formed in the other end of the ribbon. The straitjacket may be held in the locked configuration by passing the tab <NUM> through the slot <NUM>, and then a wire, pin, or other filament <NUM> is disposed in the tab to prevent it from slipping through the slot. When an operator wishes to release the straitjacket, the filament may be removed from the tab and then the tab will fall out of the slot, allowing release of the ends of the ribbon from one another so that the ribbon opens up, and this will release compression applied to the prosthetic valve such that the constrained region, here the atrial flange <NUM> is then allowed to self-expand.

The pin or filament may be an elongate filament that extends proximally toward the proximal end of the delivery catheter <NUM> where an operator can manually control the pin or filament. The filament may be coupled to an actuator on the proximal end of the delivery catheter that allows the operator to control the filament from a handle on the delivery catheter (not shown). The filament may be slidably disposed in a lumen of an outer shaft <NUM> to prevent entanglement and control friction. The outer shaft <NUM> may run alongside an outer surface of the delivery catheter <NUM> or the outer shaft may be disposed in a lumen or annular space of the delivery catheter. In any example, the filament may run alongside the delivery catheter or in a lumen or annular space of the delivery catheter without the outer shaft <NUM>.

In <FIG>, the filament <NUM> has been retracted proximally removing the filament from the looped tab <NUM> allowing it to disengage from slot <NUM> thereby releasing the straitjacket and opening so the atrial flange can self-expand while the ventricular portion remains collapsed by the capsule. The straitjacket may be sutured <NUM> or otherwise attached to the prosthetic valve and therefore remains implanted with the prosthetic valve, or in any example the straitjacket may be removed from the patient. Once the atrial flange has deployed, the remainder of the prosthetic valve may be deployed similarly as previously described.

<FIG> illustrate the locking mechanism that may be used to hold the straitjacket of <FIG>. In <FIG>, the straitjacket <NUM> includes a loop formed by joining opposite ends <NUM>, <NUM> of a ribbon. One end <NUM> includes a slotted region <NUM> and the opposite end <NUM> includes a tab <NUM> with a channel <NUM> extending through the tab. The slot is sized to receive the tab and the channel has a longitudinal axis which is transverse to or substantially orthogonal to the longitudinal axis of the ribbon.

In <FIG>, the opposite ends <NUM>, <NUM> of the ribbon have been overlapped with one another and tab <NUM> is inserted into slot <NUM>. Pin or filament <NUM> is then inserted into channel <NUM> locking the straitjacket into the closed position and constraining the prosthetic valve from self-expansion. When the operator is ready, the pin or filament <NUM> may be removed from channel <NUM> which releases the straitjacket and allowing the prosthetic valve to self-expand. The straitjacket may also be referred to as a belt or cinching element/mechanism.

The straitjacket may be disposed around any one or more regions of the prosthetic valve including the atrial flange, the annular region, the anchor tabs, the ventricular skirt, etc. It may be formed from any material including metals, fabrics such as Dacron, polymers, etc..

The prosthetic valves previously described above may be modified to optionally include any of the following features which may facilitate delivery, deployment, or valve function.

For example, in any example of the valve body may be configured with a D-shaped cross-section to better fit the native valve anatomy. In still other examples, other cross-sectional shapes maybe desirable such as round, elliptical, square, rectangular, etc. to conform to, or anchor to the native anatomy.

Whether a D-shape or another shape, in some examples it may be desirable to form the prosthetic valve body so that upon expansion it does not engage the native valve annulus and thus anchoring is only accomplished via the upper atrial flange and the anchor tabs. Sizes of the anchoring elements may be adjusted to accommodate varying annular sizes. The valve body may have a perimeter that has a smaller diameter than the diameter of the perimeter of the native valve annulus. This may be advantageous for patients with small ventricles with degenerative mitral regurgitation (DMR) and a high ejection fraction.

Other expandable valve frame geometries may also provide advantages. For example, an expandable frame with fewer strut connection nodes reduces the amount of material in the prosthetic valve and thereby allows the valve frame to be collapsed into a lower profile which is desirable during delivery.

<FIG> shows an example of an expandable frame that can collapse into a smaller profile relative to earlier examples which not only helps with delivery of a smaller delivery system but also allows the frame to be more tightly crimped onto the delivery system ensuring safer delivery with less chance of the frame ejecting from the delivery system. The expandable frame <NUM> generally takes the same form as previously described in other frames above, but has less metal forming the expandable frame and therefore collapses into a lower profile which facilitates delivery and also facilitates navigation through tortuous vessels. A reduced number of diamond shaped cells in the annular region allows for the reduced crimp. The smaller profile allows the frame to be more tightly crimped onto the delivery system ensuring safer delivery. Also, the lower profile allows a smaller percutaneous puncture to be used during introduction and delivery, thereby reducing the change of vascular trauma and bleeding and potentially speeding up sealing of the puncture site after the procedure.

The expandable frame <NUM> includes an atrial region <NUM>, annular region <NUM> and ventricular region <NUM>. The atrial region <NUM> includes a plurality of elongate linear struts that are coupled together with a connector strut to form a sinusoidal pattern with peaks and valleys. The atrial region may be heat treated to form the atrial flange previously described above.

The annular region <NUM> similarly is formed from a plurality of elongate linear struts coupled together with a connector to form a sinusoidal pattern with peaks and valleys. The annular region may be round and cylindrical or have a D-shaped cross-section, or any other cross-sectional shape. Linear connector struts join the atrial region with the annular region.

The ventricular region <NUM> includes elongate linear struts connected together to form a sinusoidal pattern with peaks and valleys. Other aspects of the ventricular region are similar to those previously described in other examples of expandable frames. For example, the expandable frame includes commissure posts <NUM> with enlarged mushroom shaped heads that releasably coupled the expandable frame with the delivery catheter, and also the commissure posts allow tissue or other material to be coupled to the commissure posts to form the prosthetic valve leaflets. In some examples, the commissure posts may have differently shaped connector heads on the anterior commissure posts to allow an operator to visualize under radiography or ultrasound the prosthetic valve orientation relative to the anatomy of the native valve. For example, the posterior commissure heads may be mushroom shaped while the anterior commissure posts may have trapezoidal shaped heads. Ventricular anchors <NUM> such as anterior and/or posterior anchor tabs are also included in the expandable frame as well as a ventricular skirt <NUM>. In this example, the commissure posts are nested within struts that form the ventricular skirt. Moreover, the commissure posts do not extend past the edge of the ventricular skirt.

The frame design may also include commissure posts that are longer than the anchor tabs when crimped or collapsed onto the delivery system. This simplifies attachment to the delivery catheter and reduces the depth of contact between the commissure posts and the delivery system.

<FIG> illustrates an example of an expandable frame <NUM> with commissure posts <NUM> that extend past the edge of the ventricular skirt <NUM>. This example shows the anchoring tabs <NUM> axially shorter than the commissure posts <NUM>. Also, the commissure posts are no longer encircled by adjacent struts (ventricular arches) to simplify anchoring to the delivery system since the anchoring points are now at the furthest end of the frame. Also removed are the "S" bars. Only the support bars remain which attach directly to the commissure rail in this example. The overall shorter design (the removal of the eyelets also helps) also improves navigation of the device through tight anatomy. The removal of the ventricular arches also removes bulk near the anchoring points in the crimp state. Also, the mounting of the valve to the delivery system is more easily visualized without the arches. Other aspects of the anchor frame <NUM> are generally the same as described in <FIG> including the atrial portion <NUM> which forms an atrial flange, the annular region <NUM>, and the ventricular region <NUM>. Each of these regions includes elongate struts coupled together to form a sinusoidal pattern with peaks and valleys. The regions are coupled together with connector struts.

As disclosed previously, enlarged mushroom head regions <NUM> on the commissure posts allow the prosthesis to be disposed in recessed or slotted regions on the delivery system. An outer catheter is slidably disposed over the commissure posts thereby constraining the commissure posts in the catheter recesses and releasably engaging the prosthesis to the delivery system. Retraction of the outer catheter allows the commissure posts to be released from the recessed regions of the delivery system thereby uncoupling the prosthesis from the delivery catheter. In some examples, the free ends of the commissure posts with or without enlarged mushroom heads maybe angled radially inward or radially outward to facilitate prosthesis loading onto the delivery system and to help prevent premature release. Angling of the commissure posts also may impact valve sealing, left ventricular outflow tract (LVOT) obstruction, as well as providing desirable mechanical properties to the prosthetic valve frame. Additional disclosure regarding angle commissure posts may be found below.

Also, as previously disclosed, the connectors heads <NUM> on the commissure posts <NUM> may be mushroom heads, or they may be different from one another. For example, the anterior commissure head may have one shape (e.g. trapezoidal) while the posterior commissure heads may have a different shape so that the operator can determine the orientation of the prosthesis during delivery by visualizing the prosthesis with radiographic or ultrasound techniques.

A porous valve may also be helpful since this allows a seal to form more gradually over time rather than instantaneously upon implantation because leaking allows compliance initially. A mesh or porous material may be coupled to the ventricular skirt and flow is reduced progressively over time as tissue in grows into the mesh material.

A reduced ventricular skirt may also be employed to allow for washout. This may be accomplished by leaving some or all of the ventricular skirt uncovered and this helps prevent blood flow stasis thereby permitting more natural blood flow through the prosthetic valve and avoids or minimizes thrombus formation.

Similarly, PTFE, ePTFE, or other materials maybe coupled to various portions of the prosthetic valve to help inhibit thrombus formation and growth. For example, PTFE may be disposed along or adjacent the prosthetic leaflets including adjacent the region where the prosthetic leaflet is coupled to the commissure posts and/or expandable frame. Anti-thrombus agents may also be coupled to the prosthetic valve and delivered or eluted therefrom the reduce thrombus formation.

In still other examples the prosthetic valve leaflets may include one or two or more mobile leaflets and one or two or more stationary leaflets. The stationary leaflets may be easier to design. Prosthetic leaflet height during closing may also be easier to control. The mobility of the prosthetic leaflets may also be controlled either all together or each with a unique mobility.

In any example, it may be desirable to provide commissure posts that are angled radially inward. This may help with flow dynamics as the blood or other fluid passes through the prosthetic valve leaflets which are attached to the commissures.

<FIG> shows a prosthetic valve <NUM> with commissure posts <NUM> angled radially inward so that it is orthogonal to or transverse to the longitudinal axis of the prosthetic valve. Each post may be angled inwardly in equal amounts so that a circular line is tangent to the tips of each post, or the posts may be bent in differing amounts. In other examples, the commissure posts may be angled outwardly, or some commissure posts may be angled inwardly and some angled outwardly. In still other examples, any permutation or combination of commissure posts angled inwardly, angled outwardly, or remaining straight and substantially parallel with the longitudinal axis of the prosthetic valve frame may be used. For example, in one example one or more posterior commissure posts may be straight and substantially parallel with the longitudinal axis of the prosthetic valve frame, while the prosthetic valve also has one or more anterior commissure posts which are angled radially outward (the angled commissure post is orthogonal to or transverse to the longitudinal axis of the valve). In any example, some or all of the commissure posts may be parallel with the longitudinal axis of the prosthetic valve or the commissure posts maybe curvilinear relative to the longitudinal axis of the prosthetic valve. Thus, any variation of commissure posts may be transverse to or orthogonal to the valve longitudinal axis, or parallel, or curvilinear thereto. Commissure angle can be used to impact effective orifice area, ease of valve loading, radial force to facilitate valve sealing, potential LVOT obstruction, valve hydrodynamic performance and frame mechanical properties, and therefore angle may be adjusted during manufacturing or the commissure angle may be adjusted during implantation in a patient to provide desired performance characteristics.

The following, non-limiting examples, detail certain aspects of the present subject matter to solve the challenges and provide the benefits discussed herein, among others.

While the present disclosure focuses on the use of a prosthetic valve for treating mitral regurgitation, this is not intended to be limiting. The prosthetic valves disclosed herein may also be used to treat other body valves including other heart valves or venous valves. Examples of heart valves include the aortic valve, the tricuspid valve, or the pulmonary valve.

Claim 1:
A prosthetic valve comprising:
a radially expandable frame (<NUM>) comprising an atrial flange (<NUM>), a ventricular skirt (<NUM>), an annular region (<NUM>), and a ventricular anchor tab (<NUM>),
wherein the atrial flange (<NUM>)is disposed on one end of the expandable frame (<NUM>)and the ventricular skirt (<NUM>) is disposed on an opposite end of the expandable frame (<NUM>),
wherein the annular region (<NUM>) is disposed between the atrial flange (<NUM>) and the ventricular skirt (<NUM>),
wherein the anchor tab (<NUM>) is coupled to the ventricular skirt (<NUM>); and
a constraining element coupled to the expandable frame (<NUM>), the constraining element configured to apply a hoop force to the expandable frame (<NUM>) thereby controlling an amount of expansion or an amount of collapse of the expandable frame (<NUM>),
wherein the constraining element is an adjustable constraining element configured to apply an adjustable hoop force to the expandable frame (<NUM>),
wherein the adjustable constraining element comprises a lasso (<NUM>) disposed around a perimeter of the atrial flange,
wherein the expandable frame (<NUM>) comprises a plurality of eyelets (<NUM>) coupled to the perimeter of the atrial flange, and wherein the lasso (<NUM>) is slidably disposed through the plurality of eyelets (<NUM>).