US20140277427A1 - Prosthesis for atraumatically grasping intralumenal tissue and methods of delivery - Google Patents

Abstract

A prosthesis can comprise an expandable frame, a plurality of distal anchors and a plurality of proximal anchors. The anchors can extend outwardly from the frame. The frame can be configured to radially expand and contract for deployment within a body cavity. The frame and anchors can have one of many different shapes and configurations. For example, when the frame is in an expanded configuration, the frame can have a larger cross-sectional dimension in a middle portion of the frame and a smaller cross-sectional dimension in a proximal portion and a distal portion of the frame, wherein the middle portion is between the proximal and distal portions. As another example, the anchors can have looped ends, the entire anchor may loop out from the frame.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application claims the benefit of priority to U.S. Provisional Appl. Nos. 61/782,707, filed Mar. 14, 2013. The entire contents of the above application(s) is/are hereby incorporated by reference and made a part of this specification. Any and all priority claims identified in the Application Data Sheet, or any correction thereto, are hereby incorporated by reference under 37 CFR 1.57.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• Certain embodiments disclosed herein relate generally to prostheses for implantation within a lumen or body cavity. In particular, certain embodiments relate to expandable prostheses such as replacement heart valves, such as for the mitral valve, that are configured to atraumatically grasp intralumenal tissue.
• 2. Description of the Related Art
• Human heart valves, which include the aortic, pulmonary, mitral and tricuspid valves, function essentially as one-way valves operating in synchronization with the pumping heart. The valves allow blood to flow downstream, but block blood from flowing upstream. Diseased heart valves exhibit impairments such as narrowing of the valve or regurgitation, which inhibit the valves' ability to control blood flow. Such impairments reduce the heart's blood-pumping efficiency and can be a debilitating and life threatening condition. For example, valve insufficiency can lead to conditions such as heart hypertrophy and dilation of the ventricle. Thus, extensive efforts have been made to develop methods and apparatuses to repair or replace impaired heart valves.
• Prostheses exist to correct problems associated with impaired heart valves. For example, mechanical and tissue-based heart valve prostheses can be used to replace impaired native heart valves. More recently, substantial effort has been dedicated to developing replacement heart valves, particularly tissue-based replacement heart valves that can be delivered with less trauma to the patient than through open heart surgery. Replacement valves are being designed to be delivered through minimally invasive procedures and even percutaneous procedures. Such replacement valves often include a tissue-based valve body that is connected to an expandable frame that is then delivered to the native valve's annulus.
• Development of prostheses including but not limited to replacement heart valves that can be compacted for delivery and then controllably expanded for controlled placement has proven to be particularly challenging. An additional challenge relates to the ability of such prostheses to be secured relative to intralumenal tissue, e.g., tissue within any body lumen or cavity, in an atraumatic manner. Further challenges arise when trying to controllably deliver and secure such prostheses in a location such as at a native mitral valve.
SUMMARY OF THE INVENTION
• Embodiments of the present disclosure are directed to a prosthesis, such as but not limited to a replacement heart valve. Further embodiments are directed to methods of delivering a prosthesis into a body cavity and/or securing a prosthesis to intralumenal tissue. In some embodiments, a replacement heart valve and methods for delivering a replacement heart valve to a native heart valve, such as a mitral valve, are provided.
• In some embodiments a prosthesis can comprise an expandable frame, a plurality of distal anchors and a plurality of proximal anchors. The anchors can extend outwardly from the frame. The frame can be configured to radially expand and contract for deployment within the body cavity. In some embodiments, when the frame is in an expanded configuration, the frame can have a larger cross-sectional dimension in a middle portion of the frame and a smaller cross-sectional dimension in a proximal portion and a distal portion of the frame, wherein the middle portion is between the proximal and distal portions. In some embodiments, at least some of the anchors comprise a loop that forms an atraumatic end of a corresponding anchor.
• In some embodiments, a prosthesis can be configured to atraumatically grasp intralumenal tissue when deployed within a body cavity. The prosthesis can comprise an expandable frame comprising a proximal end and a distal end and having a longitudinal axis extending between the proximal end and the distal end. The frame can be configured to radially expand and contract for deployment within the body cavity, wherein when the frame is in an expanded configuration, the frame has a larger cross-sectional dimension in a middle portion of the frame and a smaller cross-sectional dimension in a proximal portion and a distal portion of the frame, wherein the middle portion is between the proximal and distal portions. The prosthesis can also include a plurality of generally distally extending anchors extending from the proximal portion of the frame and configured so that when the frame is in an expanded configuration each distally extending anchor has an end positioned radially outward from the middle portion of the frame, and a plurality of generally proximally extending anchors extending from the distal portion of the frame and configured so that when the frame is in an expanded configuration each proximally extending anchor has an end positioned radially outward form the middle portion of the frame and axially spaced from the ends of the distally extending anchors. At least some of the anchors can comprise a loop that forms an atraumatic end of the anchor The frame can be configured such that radial expansion of the frame causes the ends of the plurality of distally extending anchors and the ends of the plurality of proximally extending anchors to draw closer together.
• A prosthesis according to certain embodiments can be configured to atraumatically grasp intralumenal tissue when deployed within a body cavity. The prosthesis can comprise an expandable frame, a plurality of proximal anchors each connected to the frame so that when the frame is in an expanded configuration an end of each proximal anchor is positioned radially outward from the frame and extends generally distally, and a plurality of distal anchors each connected to the frame so that when the frame is in an expanded configuration an end of each distal anchor is positioned radially outward from the frame and extends generally proximally, wherein the ends of the distal anchors are axially spaced from the ends of the proximal anchors when the frame is in an expanded configuration. In some embodiments, at least some of the anchors can comprise a looped end.
• Alternatively, or in addition, in some embodiments, at least some of the anchors can comprise a loop. Each loop of these later embodiments can comprise first through fourth segments and an arcuate segment. The first and second segments can both extend in a first generally axial direction away from the frame. The third and fourth segments can extend radially outward from the frame in a second direction generally opposite the first direction, the third segment connected to the first segment and the fourth segment connected to the second segment. The arcuate segment can connect the third segment and the fourth segment that forms an atraumatic end of a corresponding anchor. In some embodiments, the frame is configured such that radial expansion of the frame causes the ends of the plurality of proximal anchors and the ends of the plurality of distal anchors to draw closer together.
• In some embodiments, a prosthesis can be configured to atraumatically grasp intralumenal tissue when deployed within a body cavity. The prosthesis can comprise an expandable frame, a plurality of proximal anchors, and a plurality of distal anchors. The expandable frame can comprise a proximal end and a distal end and having a longitudinal axis extending between the proximal end and the distal end, the frame configured to radially expand and contract for deployment within the body cavity. The plurality of proximal anchors can each connect to the frame so that when the frame is in an expanded configuration an end of each proximal anchor is positioned radially outward from the frame and extends generally distally. The plurality of distal anchors can each connect to the frame so that when the frame is in an expanded configuration an end of each distal anchor is positioned radially outward from the frame and extends generally proximally, wherein the ends of the distal anchors are axially spaced from the ends of the proximal anchors when the frame is in an expanded configuration. At least some of the anchors can comprise a loop. Each of the anchors that comprises a loop can comprise at least a first segment extending in a first generally axial direction away from the frame, and a second segment and a third segment extending radially outward from the frame in a second direction generally opposite the first direction and coming together in an atraumatic end. The frame can be configured such that radial expansion of the frame causes the ends of the plurality of proximal anchors and the ends of the plurality of distal anchors to draw closer together.
• According to some embodiments a prosthesis can be configured to atraumatically grasp intralumenal tissue when deployed within a body cavity. The prosthesis can comprise an expandable frame comprising a proximal end and a distal end and having a longitudinal axis extending between the proximal end and the distal end, the frame configured to radially expand and contract for deployment within the body cavity, a plurality of proximal anchors each connected to the frame so that when the frame is in an expanded configuration an end of each proximal anchor is positioned radially outward from the frame and extends generally distally, and a plurality of distal anchors each connected to the frame so that when the frame is in an expanded configuration an end of each distal anchor is positioned radially outward from the frame and extends generally proximally, wherein the ends of the distal anchors are axially spaced from the ends of the proximal anchors when the frame is in an expanded configuration. At least some of the anchors can comprise a loop and each loop can comprise first through fourth segments and an arcuate segment. The first and second segments can both extend in a first generally axial direction away from the frame. The third and fourth segments can extend radially outward from the frame in a second direction generally opposite the first direction, the third segment connected to the first segment and the fourth segment connected to the second segment. The arcuate segment can connect the third segment and the fourth segment that forms an atraumatic end of a corresponding anchor. The frame can be configured such that radial expansion of the frame causes the ends of the plurality of proximal anchors and the ends of the plurality of distal anchors to draw closer together.
• Methods of delivering a prosthesis and/or securing the prosthesis to intralumenal tissue are also provided. In one embodiment, a method of delivering a replacement valve to a native mitral valve can comprise one or more of the following steps. Delivering a replacement valve mounted on a delivery device to the native mitral valve annulus while the replacement valve is in a radially compacted state, the replacement valve comprising a radially expandable frame comprising a proximal end, a distal end, a plurality of distal anchors extending generally proximally from the frame, and a plurality of proximal anchors extending generally distally from the frame. Positioning the replacement valve so that ends of the distal anchors are on a ventricular side of the native leaflets beyond a location where chordae tendineae connect to free ends of the native leaflets. Releasing at least a portion of the replacement valve from the delivery device to thereby expand the distal anchors radially outwardly to a first radial dimension. Moving the ends of the distal anchors toward the ventricular side of the native valve annulus with the distal anchors extending between at least some of the chordae tendineae to provide tension on the chordae tendineae. Further releasing the replacement valve from the delivery device to thereby expand the proximal anchors radially outwardly to a second radial dimension greater than the first radial dimension, wherein the proximal anchors upon further release of the replacement valve from the delivery device move into engagement with tissue on an atrial side of the native valve annulus while the distal anchors provide tension on the chordae tendineae.
BRIEF DESCRIPTION OF THE DRAWINGS
• These and other features, aspects and advantages are described below with reference to the drawings, which are intended to illustrate but not to limit the invention. In the drawings, like reference characters denote corresponding features consistently throughout similar embodiments.
• FIG. 1A is a side view of an embodiment of a prosthesis.
• FIG. 1B is a flat pattern view of the prosthesis ofFIG. 1A.
• FIG. 2A is a side view of an embodiment of a prosthesis.
• FIG. 2B is a flat pattern view of the prosthesis ofFIG. 2A.
• FIG. 3A is a side view of an embodiment of a prosthesis.
• FIG. 3B is a flat pattern view of the prosthesis ofFIG. 3A.
• FIG. 4 is a side view of an embodiment of a prosthesis.
• FIG. 5 is a side view of an embodiment of a prosthesis.
• FIG. 6A is a side view of an embodiment of a prosthesis configured as a replacement heart valve.
• FIG. 6B is a bottom view of the prosthesis similar ofFIG. 6A.
• FIG. 7 is a side view of an embodiment of a prosthesis configured as a replacement heart valve.
• FIG. 8A is a side view of an embodiment of a prosthesis.
• FIG. 8B is a detail view of a portion of the prosthesis ofFIG. 8A.
• FIG. 9A is a side view of an embodiment of a prosthesis.
• FIG. 9B is a bottom view of the prosthesis ofFIG. 9A, configured as a replacement heart valve.
• FIG. 10 is a schematic representation of a prosthesis positioned within the heart.
• FIG. 10A is a detail schematic representation of the prosthesis positioned within the heart ofFIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• The present specification and drawings provide aspects and features of the disclosure in the context of several embodiments of prostheses, replacement heart valves, delivery devices and methods that are configured for use in the vasculature of a patient, such as for replacement of natural heart valves in a patient. These embodiments may be discussed in connection with replacing specific valves such as the patient's aortic or mitral valve. However, it is to be understood that the features and concepts discussed herein can be applied to products other than heart valve implants. For example, the controlled positioning, deployment, and securing features described herein can be applied to medical implants, for example other types of expandable prostheses, for use elsewhere in the body, such as within a vein, or the like. In addition, particular features of a valve, delivery device, etc. should not be taken as limiting, and features of any one embodiment discussed herein can be combined with features of other embodiments as desired and when appropriate.
• With initial reference toFIG. 1A, an embodiment of aprosthesis10 is shown. The illustratedprosthesis10 includes aframe20 that may be self-expanding or balloon expandable. The prosthesis may further include a replacement valve that can be designed to replace a damaged or diseased native heart valve such as a mitral valve. The replacement valve is not shown in this embodiment as to more clearly illustrate features of theframe20, though it will be understood that a replacement valve is not required as part of the prosthesis. In addition, it will be understood that only a front portion of theframe20 is shown for further ease of illustration.
• Theframe20 can be made of many different materials, but is preferably made from metal. In some embodiments, theframe20 can be made from a shape memory material, such as nitinol. A wire frame or a metal tube can be used to make the frame. The wire frame of a metal tube can be cut or etched to remove all but the desired metal skeleton. In some embodiments a metal tube is laser cut in a repeating pattern to form the frame.FIG. 1B illustrates the flat cut pattern of the frame shown inFIG. 1A. The flat pattern can be cut from a metal tube and then the tube can be bent and expanded to the shape shown inFIG. 1A. Theframe20 can further be expanded and/or compressed and/or otherwise worked to have the desired shape or shapes, such as for introduction and implantation.
• As shown, the frame when in an expanded configuration, such as in a fully expanded configuration, has a bulbous or slightly bulbous shape, with a middle portion being larger than the proximal32 and distal34 ends. In some embodiments, the inside diameter of the both ends can be the same, or it can be bigger on one end than the other, while still having a middle portion larger than both the proximal and distal ends. In some embodiments, the effective diameter of the distal frame end is smaller than the effective diameter of the middle portion. The bulbous shape of the frame can advantageously allow the frame to engage a native valve annulus or other body cavity, while spacing the inlet and outlet from the heart or vessel wall. This can help reduce undesired contact between the prosthesis and the heart or vessel, such as the ventricular wall of the heart. In other embodiments, the frame may not have a bulbous portion, and can have substantially the same outer dimension along its entire length, or it may have one end larger than the other end. Theprosthesis10 andframe20 may be similar to the replacement heart valves and associated frames disclosed in U.S. Pat. No. 8,403,983 and U.S. Publication Nos. 2010/0298931, 2011/0313515 and 2012/0078353 the entireties of each of which are hereby incorporated by reference and made a part of this specification. This is inclusive of the entire disclosure and is not in any way limited to the disclosure of the replacement heart valves and associated frames.
• A number of struts collectively make up theframe20.FIG. 1 illustrates the frame in an expanded configuration with a number oflongitudinal struts12 and undulating struts14, with cells defined by the open spaces between the struts. The longitudinal struts may be arranged so that they are parallel or generally or substantially parallel to a longitudinal axis of the frame. The longitudinal axis of the frame may be defined as the central axis that extends through the center of the frame between the proximal32 and distal34 ends. Any number of configurations of struts can be used, such as the rings of undulating struts shown forming chevrons and diamonds, but also ovals, curves, and various other shapes. The illustrated embodiment includes two rings, or rows of chevrons shown inportion16 and two rows of diamond-shaped cells shown inportion18.
• Theframe20 has anon-foreshortening portion16 and aforeshortening portion18. These portions can be defined by theframe20 and the positioning of various types of struts along theframe20. InFIG. 1 it can be seen that thelongitudinal struts12 span the length of thenon-foreshortening portion16, while undulatingstruts14 form theforeshortening portion18. When the frame is radially collapsed or compacted, thestruts14 become more parallel with respect to the longitudinal axis of the frame, causing an outer diameter of the frame to decrease and the longitudinal length of the frame to increase in theforeshortening portion18. As the frame moves from a compacted position to an expanded position, the longitudinal length of the frame can decrease in theforeshortening portion18. But, the frame length does not substantially change length in thenon-foreshortening portion16.
• Foreshortening of theframe20 can be used to engage and secure the prosthesis to intralumenal tissue in a body cavity, for example tissue at or adjacent a native valve, such as a native valve annulus and/or leaflets. Opposinganchors22,24 can be constructed on theframe20 so that portions of the anchors, such as tips or ends26,28, move closer together as the frame foreshortens. As one example, this can allow theanchors22,24 to grasp tissue on opposite sides of the native mitral annulus to thereby secure the prosthesis at the mitral valve.
• Theanchors22,24 andanchor tips26,28 can be located anywhere along theframe20 just so long as at least one of the anchors is either connected to theforeshortening portion18 or the foreshortening portion is positioned between the anchors so that a portion of the anchors will be move closer together with expansion of the frame. As shown, theanchors24 are connected to theforeshortening portion18. The foreshortening portion can also be positioned anywhere along the frame, though it is shown towards thedistal end34. In some embodiments, both of theanchor tips26,28 are located in theforeshortening portion18. In some embodiments, the foreshorteningportion18 may extend the entire length of the frame, such that there is nonon-foreshortening portion16.
• Preferably, each of theanchors22,24 is positioned or extends generally radially outwardly from theframe20 so that theanchor tips26,28 are generally spaced away or radially outward from the rest of theframe20. For example, the anchor tips may be located radially outward from the middle portion of the frame, with thetips26 and28 being axially spaced from one another. In some embodiments, all or part of the structure connected to the anchor tip and extending radially from the frame, including one or more rings and/or struts, can be considered part of the anchor. The anchors can include a base located on the anchor on a side opposite the tip. The base can be for example where the anchor begins to extend from or away from theframe20.
• For example,proximal anchors22 are shown having first36 and second38 struts forming a chevron and connected tolongitudinal struts12 at a base of the anchor. The first and second struts of theanchor22 are bent at the base so that theanchor22 extends radially outwardly from the frame as it extends generally distally towards thetip26. The first and second struts can be connected to each other at a radially outward location to form an outwardly extending loop, and in some embodiments, the first and second struts can be joined at athird strut40 that continues to extend outwardly and/or generally distally. Here thethird strut40 is a short strut. The anchor also includes aneyelet46. As illustrated, the eyelet is located at thedistal end26, though the eyelet can be positioned in other locations along theanchor22. Thetips26 of the proximal anchors may extend distally and be parallel or substantially parallel with the longitudinal axis of the frame, or as illustrated inFIG. 1A, thetips26 may extend generally distally but still radially outwardly inclined or at an acute angle relative to the longitudinal axis of the frame.
• As another example, thedistal anchors24 are shown having looped ends48. The looped ends can be larger near the tip to form a type of elongated teardrop. In addition, thetips28 may be substantially flat. The looped end may assist the frame in not getting caught up on structures at or near the treatment location. For example, each loop can be configured so that when the frame is deployed in-situ and expands, the movement of each loop from a delivered position to a deployed position can avoids getting caught on the papillary muscles.
• Eachdistal anchor24 is connected to the frame at abase42. As illustrated inFIG. 1A, the base of the distal anchor may be at a location where the corners of adjacent cells meet, such that the base is proximal to thedistal end34 of the frame. In other embodiments, the base of the distal anchor may be at a distal most corner of a cell, which corresponds to a distal most point on the frame The distal anchors as illustrated extend from the base42 generally distally before bending back around in an arcuate segment where the distal anchor extends generally proximally and radially outwardly from the frame. As shown, theanchors24 may also generally distally and radially inwardly with respect to the frame such that the distal most point on the prosthesis has a smaller inside diameter than where thebase42 connects to the frame. The inside diameter at the distal most can be the same or substantially the same as the inside diameter of the proximal end, or may be smaller. The anchor as illustrated is bent around about 180 degrees so that thetip28 extends in the opposite, proximal direction, which may be parallel or substantially parallel to the longitudinal axis of the frame. For example, inFIG. 1A it can be seen that thedistal anchors24 are bent further inward such that the ends of the anchors point proximally and are generally parallel with the longitudinal axis of the frame. Alternatively, thetip28 may extend generally proximally but still extend radially outwardly inclined or at an acute angle relative to the longitudinal axis of the frame
• It will be understood that the anchors can have various other configurations, including the various embodiments that follow. In some embodiments, each of the anchors can extend radially outwardly from the frame at an anchor base and terminate at an anchor tip. The anchors can be connected to the frame at one of many different locations including apices, junctions, other parts of struts, etc. The anchors can comprise first, second, third, or more spaced apart bending stages along the length of each anchor. The anchors can also extend either distally or proximally before and/or after one or more of the bending stages. A portion of the anchor may extend with the frame before or after any bending stages.
• In the illustrated embodiment ofFIG. 1A-B there are twelve distal anchors and twelve proximal anchors. In some embodiments there may be 6 anchors on one side and 12 on the other. Some embodiments may include different numbers of anchors. In addition, the distal and proximal anchors may be aligned so the tips point generally towards each other, or they may be spaced so that the tips point between two tips on the opposite side, as is illustrated inFIGS. 1A-B.
• Theanchor tips26 and28 as described above advantageously provide atraumatic surfaces that may be used to grasp intralumenal tissue without causing unnecessary or undesired trauma to tissue. For example, theproximal anchors tips26 anddistal anchor tips28 may form flat, substantially flat, curved or other non-sharp surfaces to allow the tips to engage and/or grasp tissue, without necessarily piercing or puncturing through tissue.
• FIGS. 2A-3B show prostheses similar to that ofFIGS. 1A-B with two different styles ofdistal anchors24. InFIGS. 2A-B, the loopedend48′ of the distal anchor is generally more elliptical with a curved tip as compared to the elongated teardrop shape of loopedend48 ofFIGS. 1A-B. Otherwise the shape is substantially the same.
• InFIGS. 3A-B, thedistal anchors24 are looped anchors rather than having looped ends. The looped anchor has afirst base42 and asecond base44 connected to the frame, wherein the first and second bases are at opposite corners of the same cell. Alternatively, the first and second bases may be located at the distal most corners of adjacent cells. The distal anchors24 extends generally distally from the frame at thefirst base42 but then is bent back around and begins to extend outwardly from the frame in a generally proximal direction. Thedistal anchor24 then repeats this configuration in reverse towards thesecond base44 such that the two sides of the looped anchor are mirror images of one another. It will be understood that the looped anchor can have other configurations and that it may not be symmetrical.
• As illustrated inFIG. 3A, thetips28 of the distal anchors are circumferentially aligned with thetips26 of the proximal anchors, though in other embodiments, thetips28 of the distal anchors may be circumferentially staggered between thetips26 of the proximal anchors. In the embodiment ofFIG. 3A, adjacentdistal anchors26 are spaced apart by one cell, though in other embodiments, adjacent distal anchors may be provided on adjacent cells. Thus, for example, instead of having six distal anchors and twelve proximal anchors as shown inFIG. 3A, there may be a 1:1 correspondence between proximal and distal anchors.
• The illustrated looped distal anchor ofFIGS. 3A-B is made up of the following segments. Thefirst segment50 extends generally longitudinally with the frame, extending distally or generally distally (e.g., slightly radially inward) with the frame. The strut is then bent so that asecond segment52 extends generally parallel with an adjacent undulatingstrut14. The strut is then bent so that athird segment54 begins to extend generally longitudinally and distally or generally distally, and then is bent back around to point in generally the opposite direction (e.g., in a proximal direction parallel or generally parallel with the longitudinal axis of the frame). Thethird segment54 ends in the roundedtip28 and then the anchor strut repeats to form the mirror image. After thethird segment54 bends back around to point in generally the opposite direction, in the embodiment illustrated the third segment may first extend radially outward at an acute angle relative to the longitudinal axis before bending into a portion that extends parallel or substantially parallel to the longitudinal axis. The pairedthird segments54 extend parallel or generally parallel with one another from the second segment to the tip, though they may also move slightly towards or away from each other in some embodiments.
• FIG. 4 shows a prosthesis similar toFIGS. 3A-B that also has looped distal anchors. In this embodiment thefirst segment50 extends longitudinally in a distal direction from the frame and the strut is bent back on itself to point generally in the opposite (e.g., proximal) direction. The second segment is bent inward before extending parallel or generally parallel with its mirror image on the other side forming a nose and wing configuration similar to the shape of certain bicycle seats.
• The proximal anchors22 also have an elongatedthird strut40. Theproximal anchor22 is shown having first36 and second38 struts forming a chevron and connected tolongitudinal struts12 at a base of the anchor. The first and second struts of theanchor22 are bent at the base so that theanchor22 extends radially outwardly from the frame as it extends towards thetip26. The first and second struts join at athird strut40 that continues to extend outwardly and is then bent such that the tip points distally and extends in a manner parallel or generally parallel with the longitudinal axis of the frame. The proximal anchor may or may not include aneyelet46 along its length. The distal tip of the proximal anchors may have an atraumatic surface, such as an enlarged circular or curved end as illustrated. When the frame is in an expanded configuration, thedistal anchors24 may havetips28 that are positioned radially outward of thetips26 of the proximal anchors22. Other embodiments may have thetips26 being positioned outward of thetips28. Such configurations are also possible with the other frames and prostheses described elsewhere herein.
• FIG. 5 illustrated an embodiment similar to the prosthesis ofFIG. 4 with twelve distal anchors instead of six. Because of this change, in one embodiment two anchors share thefirst segment50 where theanchor base42,44 is connected to the frame. As illustrated, each of the proximal and distal anchors may be circumferentially aligned with each other, and each of the distal anchors corresponds to one of the cells
• Turning now toFIGS. 6A-B, prosthesis and frame embodiments are shown similar to that ofFIG. 4, including various other components of the prosthesis. A prosthesis can include one or more of avalve60, askirt70 and asupport band80. The prosthesis can be a replacement heart valve similar to that and including features similar to those disclosed in U.S. patent application Ser. Nos. 13/165,721, filed Jun. 21, 2011, published as U.S. 2011/0313515; and 13/244,080, filed Sep. 23, 2011, published as 2012/0078353. The entire contents of both applications are hereby incorporated by reference herein and made a part of this specification. This is inclusive of the entire disclosure and is not in any way limited to the disclosure of the replacement heart valve.
• Thevalve60 can be a replacement heart valve which includes a plurality ofvalve leaflets62. The plurality ofvalve leaflets62 can function in a manner similar to the natural mitral valve, or to other valves in the vascular system. The plurality ofvalve leaflets62 can open in a first position and then engage one another to close the valve in a second position. The plurality ofvalve leaflets62 can be made to function as a one way valve such that flow in one direction opens the valve and flow in a second direction opposite the first direction closes the valve. Thereplacement heart valve60 can be constructed so as to open naturally with the beating of the heart. For example, the plurality ofvalve leaflets62 can open during diastole and close during systole.
• In some embodiments, theleaflets62 can be coupled to askirt70. For example, the proximal ends of theleaflets62 can be connected to a proximal end of theskirt70.
• Theskirt70 can be used to at least partially control how fluid flows through and/or around thevalve60. Theskirt70 can surround at least a portion of the valve and be connected to thevalve leaflets62. In some embodiments, theskirt70 can form an inner wall connected to and positioned within theframe20. Theskirt70 can also be made to move with theforeshortening portion18 of theframe20.
• Theskirt70 can extend the length of theframe20 or it can extend along only part of the length of theframe20. In some embodiments, the ends of theheart valve60 can coincide with ends of theskirt70. In addition, one or more of the ends of theframe20 can coincide with the ends of theskirt70. In the illustrated embodiment ofFIGS. 6A-B, the proximal end of theskirt70 andheart valve60 are sewn together. Theskirt70 can not only extend to the distal end of theframe20 but can also extend to the outside of the frame and is shown wrapped around each of the distal anchors24.
• Other shapes and configurations can also be used for thevalve60 andskirt70. In some embodiments, theskirt70 may extend along the length of theleaflets62, but is not connected to them. In the illustrated embodiments, theskirt70 is attached to theframe20 and theleaflets62 are attached to theskirt70.
• Theskirt70 can be constructed in multiple different ways. Theskirt70 can be made of knit polyester or another stretchable or flexible fabric. In some embodiments, theskirt70 is made from a material that is more flexible than the valve leaflet material. The distal and/or proximal end of theskirt70 can be straight, curved, or have any other desired configuration. For example, theskirt70 is shown with undulations patterned to generally correspond to the undulations at thedistal end34 of theframe20. It can be seen that theskirt70 wraps around the struts at the distal end. Theskirt70 can be formed of one piece or multiple pieces. For example, theskirt70 attached to thevalve60 can be one piece and then each distal anchor can be covered by a separate piece of material of theskirt70. It is to be understood that other configurations of theskirt70 can also be employed. For example, the anchors may remain uncovered, or only a portion may be covered.
• Turning now toFIG. 7, another embodiment of theskirt70 is shown. Here rather than theskirt70 corresponding to the undulations at thedistal end34 of theframe20, the skirt extends past the frame and is then wrapped around it. Thus, theskirt70 extends from the inside of theframe20 to the outside of the frame. The skirt can extend completely around the frame for ¼, ⅓, ½, or more of the length of the distal anchors. The skirt can also cover the distal anchors24. In the illustrated embodiment, the skirt is a one piece skirt, but it will be understood that the skirt can be made of multiple pieces.
• Theskirt70, and particularly portions that cover thedistal anchors24, can beneficially be used to help prevent leakage of blood flow around the heart valve. In addition, the skirt can encourage tissue in-growth between the skirt and the natural tissue. This may further help to prevent leakage of blood flow around the heart valve.
• Theprosthesis10 can also include asupport band80 as is shown inFIGS. 6A-7. Thesupport band80 may be placed or positioned around or within theframe20 at theproximal end32. Thesupport band80 can be used to reinforce and/or constrain theframe20. Thesupport band80 can help to control the expansion of theframe20 from the compacted to the expanded state. Thesupport band80 can also be used to reduce the amount of motion that occurs at theproximal end32 after theprosthesis10 has been implanted at the mitral heart valve or other location.
• In some embodiments, thesupport band80 may comprise a polyester fabric band. Thesupport band80 may comprise a no-stretch or limited stretch material. Preferably thesupport band80 is not made of an elastic material or a material known to have high elasticity. In some embodiments, thesupport band80 is made from a material that is less flexible than the valve skirt material and/or the valve leaflet material. The distal and proximal ends of thesupport band80 can be straight, curved, undulating with the undulations of frame, or any other desired configuration.
• Thesupport band80 can be connected to the valve frame with a plurality of stitches, loops, knots, staples, or other types of connections. In some embodiments, theframe20 can be sandwiched between two sides or layers of thesupport band80. Preferably, thesupport band80 is a single layer positioned within and attached to theframe20 with a plurality of stitches around one or more of the longitudinal and/or undulating struts. In some embodiments, thesupport band80 can be attached to the proximal end of thevalve skirt40.
• Looking now atFIGS. 8A-B another embodiment of aprosthesis10 is shown.FIGS. 8A-B show a prosthesis similar to that ofFIG. 4 with a different style and configuration ofdistal anchor24. InFIGS. 8A-B, the distal anchors are shorter than and spaced radially inward from the distal anchors ofFIG. 4. Thus, as illustrated, thedistal anchors24 are not positioned as far radially outward as the proximal anchors, and thetips28 may be positioned radially inward of thetips26. As described further below, such a configuration may be advantageous in positioning and securing the prosthesis in a mitral valve or other body location. As shown particularly inFIG. 8B, thedistal anchors24 may comprise loops as described above, having a curved or arcuate atraumatic tip to minimize damage to body tissue.
• FIGS. 9A-B show an embodiment of a prosthesis where the distal anchors do not comprise loops, but instead comprise single struts each extending distally from the corners where adjacent cells meet. As described with respect to embodiments above, these anchors may first extend distally or generally distally, and may further extend radially inward, before bending around to extend proximally or generally proximally, such as at an acute angle relative to the longitudinal axis of the frame. Thetips28 of the anchors may comprise an atraumatic surface, such as a flattened or curved enlarged tip. As illustrated, thetips28 may be circumferentially staggered betweentips26 of the proximal anchors22, as best shown inFIG. 9B.FIG. 9B also shows theframe20 having avalve60 andskirt70 attached as described above.
• In preferred embodiments, any of theprostheses10 described above may be deployed into a heart valve annulus, and positioned when compacted so that theanchor tips26,28 of the opposinganchors22,24 are disposed on opposite sides of thenative annulus88 as shown inFIGS. 10 and 10A. As thereplacement heart valve10 is expanded, the opposing anchors are drawn closer together so as to grasp tissue on opposite sides of thenative annulus88 and securely hold thereplacement heart valve10 in position. As such, thereplacement heart valve10 can be held securely in position without requiring a substantial radial force against the native annulus. Because the anchor tips are preferably atraumatic, the grasping or engaging of tissue by the prosthesis minimizes damage to the native tissue. The foreshorteningportion18 can be used to move theanchor tips26,28 closer together as thereplacement heart valve10 moves to the expanded position to thereby engage the native valve annulus. The prosthesis can be deployed into a heart valve or otherwise deployed in manners similar to those described with respect to a replacement heart valve in U.S. Publication No. 2010/0298931 and 2012/0078353 the entireties of each of which are hereby incorporated by reference and made a part of this specification. This is inclusive of the entire disclosure and is not in any way limited to the disclosure related to deployment of a replacement heart valve.
• FIGS. 10 and 10A show a schematic representation of thereplacement heart valve10 installed in ahuman heart84. The heart is shown in cross-section, and represents typical anatomy, including aleft atrium78 andleft ventricle86. Theleft atrium78 andleft ventricle86 communicate with one another through amitral annulus88. Also shown schematically is a native anteriormitral leaflet90 havingchordae tendineae92 that connect a downstream end of the anteriormitral leaflet90 and to theleft ventricle86.
• In one preferred embodiment, a method is provided of delivering a replacement valve to a native mitral valve and atraumatically securing the replacement valve relative to the nativemitral valve annulus88. The replacement valve can be mounted on a delivery device and delivered to the native mitral valve annulus while the replacement valve is in a radially compacted state. The replacement valve may be positioned so that the ends or tips of the distal anchors are on a ventricular side of thenative leaflets90 beyond a location wherechordae tendineae92 connect to free ends of the native leaflets. At least a portion of the replacement valve can be released from the delivery device to thereby expand the distal anchors radially outwardly. At this time the distal anchors may extend between at least some of the chordae. The distal anchors (along with the frame) can be moved toward the ventricular side of the native valve annulus with the distal anchors extending between at least some of the chordae tendineae to provide tension on the chordae tendineae. With tension provided on the chordae tendineae, the replacement valve can be further released from the delivery device to thereby expand the proximal anchors radially outwardly. The proximal anchors upon further release of the replacement valve from the delivery device can move into engagement with tissue on an atrial side of the native valve annulus, such as with the atrial side of the native valve annulus.
• The method just described may utilize any of the prostheses herein described, but may be particularly suitable for the prosthesis ofFIGS. 8A-8B where the ends of the distal anchors are not positioned as far out radially as the ends of the proximal anchors when the frame is expanded. Thus, the distal anchors may have a suitable length for extending between and providing tension on the chordae tendineae, but need not and may not in some embodiments engage tissue with thetips28. Thus, in some embodiments the some or all of the distal anchors remain spaced from tissue on the ventricular side of the native valve annulus after delivery and expansion. The interaction between the distal anchors and the chordae tendineae may therefore be sufficient to secure the distal end of the prosthesis, while the engagement of the proximal anchors with tissue on the atrial side of the native valve annulus will help further secure and orient the prosthesis
• As illustrated inFIGS. 10 and 10A, the distal anchors may comprise loops, such as any of the looped structures previously described. The distal anchors may also be covered with a resilient material such as described above for theskirt70 that promotes tissue growth with adjacent body tissue. Such material may also be useful to prevent paravalvular leakage. The atraumatic distal anchors may advantageously prevent snagging of the prosthesis on internal structures, such as the papillary muscles.
• Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while a number of variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.
• Similarly, this method of disclosure, is not to be interpreted as reflecting an intention that any claim require more features than are expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in a combination of fewer than all features of any single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment.

Claims (21)

1-31. (canceled)

32. A prosthesis configured to atraumatically engage intralumenal tissue when deployed within a body cavity, the prosthesis comprising:

an expandable frame comprising a proximal end and a distal end and having a longitudinal axis extending between the proximal end and the distal end, the frame configured to radially expand and contract for deployment within the body cavity; and

a plurality of distal anchors each connected to the frame at a base and having a looped atraumatic end;

wherein when the frame is in an expanded configuration:

each of the plurality of distal anchors extends from the base generally distally before extending generally proximally and radially outwardly from the frame; and

the looped atraumatic end of each distal anchor is circumferentially aligned with the base where the distal anchor connects to the frame so that the looped atraumatic end and the base are both located within a common plane that is parallel to and intersects the longitudinal axis.

33. The prosthesis ofclaim 32, wherein the frame comprises a plurality of cells formed by interconnected struts.

34. The prosthesis ofclaim 33, wherein when the frame is in an expanded configuration, a width of each of the plurality of distal anchors as defined circumferentially around the longitudinal axis over the entire length of the distal anchor from the base to the looped atraumatic end is less than the width of one cell.

35. The prosthesis ofclaim 33, wherein the base of each of the plurality of distal anchors is at a location where corners of two adjacent cells meet.

36. The prosthesis ofclaim 33, wherein the base of each of the plurality of distal anchors is at a distalmost corner of a cell.

37. The prosthesis ofclaim 33, wherein adjacent looped ends of the plurality of distal anchors are spaced apart by at least one cell.

38. The prosthesis ofclaim 32, further comprising a plurality of proximal anchors each connected to the frame, wherein when the frame is in an expanded configuration an end of each of the plurality of proximal anchors is positioned radially outward from the frame and extends generally distally so that the ends of the plurality of distal anchors are axially spaced from the ends of the proximal anchors, and wherein the frame is configured such that radial expansion of the frame causes ends of the plurality of proximal anchors and the ends of the plurality of distal anchors to draw closer together.

39. The prosthesis ofclaim 38, wherein the ends of the plurality of distal anchors are positioned radially outward from the ends of the plurality proximal anchors when the frame is in an expanded configuration.

40. The prosthesis ofclaim 38, wherein the ends of the plurality of distal anchors are not circumferentially aligned with the ends of the plurality proximal anchors when the frame is in an expanded configuration.

41. The prosthesis ofclaim 38, wherein the plurality of proximal anchors each comprises a single arm that terminates in an atraumatic tip.

42. The prosthesis ofclaim 32, further comprising a valve body attached to the frame.

43. The prosthesis ofclaim 32, further comprising a layer of resilient material covering each of the looped ends to facilitate in-growth of adjacent tissue when the prosthesis is deployed within a body cavity.

44. The prosthesis ofclaim 32, wherein when the frame is in an expanded configuration, the frame has a larger cross-sectional dimension in a middle portion of the frame and a smaller cross-sectional dimension in a proximal portion and a distal portion of the frame, wherein the middle portion is between the proximal and distal portions.

45. The prosthesis ofclaim 44, wherein the plurality of distal anchors extend from the distal portion of the frame and are configured so that when the frame is in an expanded configuration, each distal anchor of the plurality of distal anchors has an end positioned radially outward from the middle portion of the frame.

46. The prosthesis ofclaim 44, wherein the proximal end and the distal end have substantially the same cross-sectional dimension.

47. A prosthesis configured to atraumatically engage intralumenal tissue when deployed within a body cavity, the prosthesis comprising:

an expandable frame comprising a proximal end and a distal end and having a longitudinal axis extending between the proximal end and the distal end, the frame configured to radially expand and contract for deployment within the body cavity; and

a plurality of distal anchors each connected to the frame at a base and having a looped atraumatic end, wherein each of the plurality of distal anchors is connected to the frame with a single strut;

wherein when the frame is in an expanded configuration each of the plurality of distal anchors extends from the base generally distally before extending generally proximally and radially outwardly from the frame.

48. The prosthesis ofclaim 47, wherein the frame comprises a plurality of foreshortening cells, and each of the plurality of distal anchors is connected to the frame with a single strut extending from one of the cells.

49. The prosthesis ofclaim 48, wherein the frame comprises a foreshortening portion and a non-foreshortening portion, wherein the foreshortening portion comprises the plurality of foreshortening cells and is distal to the non-foreshortening portion.

50. The prosthesis ofclaim 49, further comprising a plurality of proximal anchors extending radially outward from the non-foreshortening portion of the frame when the frame is in an expanded configuration.

51. The prosthesis ofclaim 47, wherein when the frame is in an expanded configuration, the frame has a larger cross-sectional dimension in a middle portion of the frame and a smaller cross-sectional dimension in a proximal portion and a distal portion of the frame, wherein the middle portion is between the proximal and distal portions.

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