Patent Publication Number: US-2022226105-A1

Title: Inverted delivery techniques for prosthetic heart valves

Description:
TECHNICAL FIELD 
     The present disclosure relates to heart valve interventional systems and methods and, more particularly, to methods for delivering and repositioning mitral valves. 
     BACKGROUND 
     Human heart valves, which include the aortic, pulmonary, mitral and tricuspid valves, function in synchronization with the pumping heart to control the flow of blood between chambers of the heart. In short, the valves allow blood to flow downstream and inhibit blood from flowing upstream. Diseased heart valves exhibit impairments such as narrowing of the valve, remodeling of the annulus, or calcification, which inhibit the valves from properly controlling blood flow. Such impairments reduce the heart&#39;s blood-pumping efficiency and can be a debilitating or, in some situations, life threatening. Thus, extensive efforts have been made to develop methods and devices to repair or replace impaired heart valves. 
     One technique for addressing a damaged or defective heart valve is to replace the native valve with a valve prosthesis. One category of heart valve prosthesis includes those that can be delivered in a minimally invasive fashion so as to minimize trauma to the patient. 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 that is connected to an expandable frame that is then delivered to the native valve&#39;s annulus. 
     Development of prostheses including but not limited to replacement heart valves that can be collapsed for minimally invasive delivery and then controllably expanded has proven to be particularly challenging. An additional challenge relates to the ability of such prostheses to be secured relative to adjacent native tissue. Adequate anchoring of the prosthesis is important to ensuring the successful operation of the prosthetic heart valve for a sufficient length of time. 
     SUMMARY 
     The present disclosure describes shapes and geometries of anchoring elements, including feet, used to secure a prosthetic valve, e.g., a prosthetic mitral valve, in the native heart valve annular position. In embodiments, the foot geometry/directionality is designed such that the foot loads to the fibrous annular region that is made of collagenous tissue with higher puncture resistance. Additionally, the foot contact surface area is designed such that the pressure exerted by the foot is below the pressure required to puncture the heart tissue, such as the left ventricular (LV) muscle wall. Further, the present disclosure provides an improved method of delivering and/or repositioning a valve dock and/or valve replacement system by inverting the implant anchors, e.g., including the feet, to point downward, i.e., toward the ventricle, while crossing the native mitral valve annulus. The valve feet are then deployed once the tips of the feet are a sufficient distance past the annulus. To reposition the valve, the frame is retracted using delivery mechanisms to return the feet to the inverted state, which can be used for removing and/or reattempting deployment of the valve. 
     As recited in examples, Example 1 is a method of delivering a valve prosthesis to be deployed within a native heart valve at a native heart valve annulus. The method including collapsing a prosthetic valve having an expandable frame comprising a proximal end and a distal end and a longitudinal axis extending therethrough inside of a delivery instrument, such that a plurality of spaced anchors extending from the distal end of the expandable frame towards the proximal end are collapsed to an inverted position in a collapsed anchor configuration. The method further including advancing the delivery instrument a first distance such that the plurality of spaced anchors extend below the valve annulus, and releasing each of the plurality of spaced anchors such that each of the plurality of spaced anchors is repositioned from the inverted position to an expanded anchor configuration to contact a subannular location 
     Example 2 is the method of Example 1, comprising adjusting an angle of each of the plurality of spaced anchors, such that upon release the spaced anchors contact the subannular location. 
     Example 3 is the method of Example 1, where releasing each of the plurality of spaced anchors includes releasing each of the plurality of spaced anchors such that each of the plurality of spaced anchors has a foot angle of from 0 to 45 degrees relative to the longitudinal axis. 
     Example 4 is the method of Example 1, wherein collapsing the prosthetic valve includes collapsing the plurality of spaced anchors to the collapsed anchor configuration, such that each of the plurality of spaced anchors pivots to an outward and progressively downward position. 
     Example 5 is the method of Example 1, wherein collapsing the prosthetic valve includes collapsing the plurality of spaced anchors such that each of the plurality of spaced anchors pivots from a foot angle of from 0 to 45 degrees to an outward and downward foot angle of from 45 to 180 degrees. 
     Example 6 is the method of Example 1, wherein the delivery instrument includes an outer catheter member attached to the expandable frame adjacent the proximal end and an inner catheter member attached to the expandable frame adjacent the distal end. 
     Example 7 is the method of Example 6, wherein collapsing the prosthetic valve includes retracting the inner catheter member into the outer catheter member to pivot each of the plurality of spaced anchors to an outward and progressively downward position. 
     Example 8 is the method of Example 6, wherein releasing each of the plurality of spaced anchors includes extending the inner catheter member out of the outer catheter member to pivot each of the plurality of spaced anchors to the expanded anchor configuration. 
     Example 9 is the method of Example 1, wherein each of the plurality of spaced anchors are locked into the collapsed anchor configuration prior to advancing the delivery instrument. 
     Example 10 is the method of Example 1, comprising at least one of repositioning and removing the valve prosthesis by collapsing the prosthetic valve, such that each of the plurality of spaced anchors collapses to the inverted position. 
     Example 11 a method of delivering a valve prosthesis to be deployed within a native heart valve at a native heart valve annulus. The method including collapsing a prosthetic valve having an expandable frame comprising a proximal end and a distal end and a longitudinal axis extending therethrough inside of a delivery instrument, such that a plurality of spaced anchors extending from the distal end of the expandable frame towards the proximal end pivot outward and downward from an expanded foot angle of from 0 to 45 degrees to a collapsed foot angle of from 45 to 180 degrees. The method further including advancing the delivery instrument such that the plurality of anchors extend below the valve annulus, and releasing each of the plurality of anchors such that each of the plurality of anchors pivots to the expanded foot angle of from 0 to 45 degrees. 
     Example 12 is the method of Example 11, where releasing each of the plurality of anchors repositions the anchors for contacting subannular tissue. 
     Example 13 is the method of Example 11, wherein the delivery instrument includes an outer catheter member attached to the expandable frame adjacent the proximal end and an inner catheter member attached to the expandable frame adjacent the distal end. 
     Example 14 is the method of Example 13, wherein collapsing the prosthetic valve includes retracting the inner catheter member into the outer catheter member to pivot each of the plurality of anchors to an inverted position. 
     Example 15 is the method of Example 13, wherein releasing each of the plurality of anchors includes extending the inner catheter member out of the outer catheter member to pivot each of the plurality of anchors to the expanded foot angle for contacting subannular tissue. 
     Example 16 is a valve prosthesis system including a prosthetic valve and a delivery instrument. The prosthetic valve having an expandable frame including a proximal end and a distal end and a longitudinal axis extending therethrough. The expandable frame configured to collapse radially for delivery and expand radially upon deployment to an expanded configuration. The prosthetic valve including a plurality of anchors extending from the distal end of the expandable frame towards the proximal end, each anchor being expandable from a collapsed anchor configuration to an expanded anchor configuration. The delivery instrument includes an outer catheter member attached to the expandable frame adjacent the proximal end and an inner catheter member attached to the expandable frame adjacent the distal end, wherein the inner catheter member is retracted into the outer catheter member to pivot each of the plurality of anchors to an inverted position in the collapsed anchor configuration. 
     Example 17 is the system of Example 16, wherein the delivery instrument is configured to release each of the plurality of anchors from the inverted position to the expanded anchor configuration. 
     Example 18 is the system of Example 16, wherein the inner catheter member is retracted into the outer catheter member to pivot each of the plurality of anchors outward and progressively downward to the inverted position. 
     Example 19 is the system of Example 16, wherein the inner catheter member is retracted into the outer catheter member to pivot each of the plurality of anchors from a foot angle of from 0 to 45 degrees to a foot angle of from 45 to 180 degrees. 
     Example 20 is the system of Example 16, wherein the inner catheter member is extended out of the outer catheter member to pivot each of the plurality of anchors to the expanded anchor configuration 
     While multiple embodiments are disclosed, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a diagram illustrating a top (atrial) view of a heart valve prosthesis configured to be deployed within a native heart valve at a native heart valve annulus, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 1B  is a diagram illustrating an anterior view of the heart valve prosthesis, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 2  is a diagram illustrating a prosthetic mitral valve annulus and anchor locations for the feet of the anchors disposed about the circumference of the prosthetic mitral valve annulus, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 3A  is a schematic diagram illustrating a mitral valve having an annulus, a transition region below the annulus, and LV muscle below the transition region. 
         FIG. 3B  is a diagram illustrating tissue at the mitral valve, including the annulus, the transition region below the annulus, and the LV muscle situated below the transition region. 
         FIG. 4  is a diagram illustrating portions of a heart valve prosthesis, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 5A  is a diagram illustrating a 30 degree foot angle of an anchor and foot with respect to the longitudinal axis of the valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 5B  is a diagram illustrating a 0 degree foot angle of an anchor and foot with respect to the longitudinal axis of the valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 6  is a diagram illustrating embodiments of the profile of a foot, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 7  is a diagram illustrating an anchor and a foot having one of the diamond-like structures as depicted in iterations C-E (shown in  FIG. 6 ), in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 8  is a diagram illustrating a native mitral valve and multiple anchor locations for the feet of a heart valve prosthesis around the circumference of the native mitral valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 9  is a diagram illustrating the delivery system attached to the prosthetic heart valve in the expanded configuration with upward facing anchoring projections having 0 to 45 degree foot angles, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 10  is a diagram illustrating the delivery system collapsing the prosthetic heart valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 11  is a diagram illustrating the delivery system further collapsing the prosthetic heart valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 12  is a diagram illustrating the delivery system further collapsing the prosthetic heart valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 13  is a diagram illustrating the delivery system further collapsing the prosthetic heart valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 14  is a diagram illustrating the delivery system further collapsing the prosthetic heart valve, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 15  is a diagram illustrating the inverted state of the prosthetic heart valve in the collapsed configuration and the outer catheter member steered and oriented and advanced towards the native mitral valve annulus, in accordance with embodiments of the subject matter of the disclosure. 
         FIG. 16  is a diagram illustrating the repositioning of the anchoring projections and the feet or the removing of the prosthetic heart valve, in accordance with embodiments of the subject matter of the disclosure. 
     
    
    
     While the disclosure is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the disclosure to the embodiments described. On the contrary, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure as defined by the appended claims. 
     DETAILED DESCRIPTION 
       FIG. 1A  is a diagram illustrating a top (atrial) view of a heart valve prosthesis  100  configured to be deployed within a native heart valve at a native heart valve annulus, in accordance with embodiments of the subject matter of the disclosure.  FIG. 1B  is a diagram illustrating an anterior view of the heart valve prosthesis  100 , in accordance with embodiments of the subject matter of the disclosure.  FIGS. 1A and 1B  illustrate the heart valve prosthesis  100  in an expanded configuration, as opposed to a collapsed configuration that is used for delivery of the heart valve prosthesis  100  to the native heart valve annulus. 
     The prosthesis  100  includes an anchor assembly  102  and a valve assembly  104 . In some embodiments, the occluding function of the prosthesis  100  can be performed using configurations other than the depicted tri-leaflet occluder. For example, bi-leaflet, quad-leaflet, or mechanical valve constructs can be used in some embodiments. 
     The anchor assembly  102  includes an expandable frame  106  having a proximal end  108  and a distal end  110  with a longitudinal axis  112  extending therethrough. The expandable frame  106  is configured to collapse radially for delivery and expand radially upon deployment to the expanded configuration. 
     The anchor assembly  102  includes a plurality of spaced anchors  114   a - 114   d  extending from the distal end  110  of the expandable frame  106  towards the proximal end  108 . Each of the anchors  114   a - 114   d  includes a free end or foot  116 .  FIGS. 1A and 1B  illustrate the anchors  114   a - 114   d  in an expanded anchor configuration for engaging subannular tissue (below the native heart valve annulus). Also, each of the anchors  114   a - 114   d  is expandable from a collapsed anchor configuration where the anchors  114   a - 114   d  are inverted such that the anchors  114   a - 114   d  point distally or downward in the collapsed anchor configuration. 
     As shown in  FIG. 1B , a supplemental covering portion  118  can be positioned on an anterior surface of the valve assembly  104 . The supplemental covering portion  118  can provide an enhanced sealing capability between the valve prosthesis  100  and surrounding native tissues. The supplemental covering portion  118  can be made of a material such as, but not limited to, DACRON®, felt, polyester, a silicone, a urethane, ELAST-EON™ (a silicone and urethane polymer), another biocompatible polymer, polyethylene terephthalate (PET), copolymers, or combinations and subcombinations thereof. In embodiments, the valve prosthesis  100  also includes a systolic anterior motion (SAM) containment member  120  with an eyelet  122  for engaging and moving the SAM containment member  120 . 
       FIG. 2  is a diagram illustrating a prosthetic mitral valve annulus  200  and anchor locations  202   a - 202   d  for the feet  116  of the anchors  114   a - 114   d  disposed about the circumference of the prosthetic mitral valve annulus  200 , in accordance with embodiments of the subject matter of the disclosure. The prosthetic mitral valve annulus  200  includes an anterior region  204 , a posterior region  206 , a commissural region  208 , and a medial/lateral region  210 . In embodiments, the prosthetic mitral valve  100  includes a SAM containment member  120  at the anterior region  204 . 
     The heart valve prosthesis  100  includes four anchors  114   a - 114   d , such that two of the anchors  114   a  and  114   d  are generally disposed at the anchor locations  202   a  and  202   d , respectively, in the anterior region  204  and two of the anchors  114   b  and  114   c  are generally disposed at the anchor locations  202   b  and  202   c , respectively, in the posterior region  206 . In embodiments, the heart valve prosthesis  100  can include three anchors, two of which are generally disposed in the anterior region  204  and one of which is disposed in a generally central location of the posterior region  206 . In other embodiments, the heart valve prosthesis  100  can include more than three or four anchors. 
     In some embodiments, the heart valve prosthesis  100  design and configuration are any one of the prosthesis designs and configurations disclosed in United States Patent Application Publication No. 2017/0189177 or United States Patent Application Publication No. 2019/0029814, which are both hereby incorporated by reference herein in their entirety. While the concepts disclosed herein may be used in conjunction with any heart valve, the following disclosure provides embodiments for a mitral valve prosthesis. 
     While the anchor locations  202   a - 202   d  are illustrated in certain locations around the circumference of the prosthetic mitral valve annulus  200  in  FIG. 2 , in embodiments, one or more of these locations can be adjusted, such as up to 10 degrees (clockwise or counterclockwise), about the circumference, i.e., perimeter, of the annulus  200 . In some embodiments, the anchor locations  202   a - 202   d  are disposed at a circumferential location about the annulus  200 , such that the anchor locations  202   a - 202   d  are generally aligned with native valve commissures. In this way, the interference of the anchors  114   a - 114   d  with the operation of the native leaflets is minimized. 
     By disposing the anchors  114   a - 114   d  at appropriate locations about the circumference of the annulus  200 , the heart valve prosthesis  100  is adequately anchored such that during diastole, when the left ventricle contracts and the blood pressure drives the valve prosthesis toward the left atrium, the anchors  114   a - 114   d  contact subannular tissue, i.e., tissue below the annulus of the native heart valve, and thereby anchor the prosthesis  100  at the mitral valve annulus location. 
       FIG. 3A  is a schematic diagram illustrating a mitral valve  300  having an annulus  302 , a transition region  304  below the annulus  302 , and LV muscle  306  below the transition region  304 . The location and size of these regions or areas may vary slightly from patient to patient. For example, in embodiments, the transition region  304  begins 1 to 3 millimeters (mm) below the annulus  302  and the LV muscle  306  begins 6 to 8 mm below the annulus  302 , and, in embodiments, the transition region  304  ends where the LV muscle  306  begins. In embodiments, the transition region  304  is about 2 millimeters (mm) below the annulus  302  and the LV muscle  306  is about 7 mm below the annulus  302 . 
       FIG. 3B  is a diagram illustrating tissue at the mitral valve  300 , including the annulus  302 , the transition region  304  below the annulus  302 , and the LV muscle  306  situated below the transition region  304 . As shown, the annulus  302  is situated between the left atrium  308  and the left ventricle  310 , and a leaflet  312  branches from the annulus  302 . 
     The annulus  302  is made up of fibrous tissue, such as collagen and/or reticular fibers, which have significantly high puncture resistance. The LV muscle substrate  306  is made up of cardiac muscle cells that have a somewhat lower puncture resistance as compared to the annulus  302 . In embodiments, the prosthetic valve anchors  114   a - 114   d  load to the tissue of the annulus  302 , the LV muscle  306 , or the transition region  304 . 
       FIG. 4  is a diagram illustrating portions of a heart valve prosthesis  400 , in accordance with embodiments of the subject matter of the disclosure. As shown, the prosthesis  400  includes anchors  402  with feet  404  for contacting tissue adjacent the native heart valve. In embodiments, the prosthesis  400  is like the heart valve prosthesis  100  of  FIGS. 1A and 1B . Also, in embodiments, the anchors  402  and feet  404  are like the anchors  114   a - 114   d  and feet  116  (shown in  FIGS. 1A and 1B ). 
     The anchors  402  and the feet  404  are configured to contact the subannular tissue on the ventricular side of the valve annulus. As shown in  FIG. 4 , the foot  404  is configured with a “foot angle”  406  defined as the angle of the foot  404  with respect to the longitudinal axis  408  of the heart valve prosthesis  400  and a “toe out distance”  410 , which is defined as the distance the foot  404  extends radially outwardly from the valve body. Additionally, the foot  404  includes a certain foot width  412  traveling through a certain arc length, which collectively defines a foot contact surface area, indicated at  414 . By adjusting these parameters, the foot contact surface area at  414  may be adjusted to an appropriate level to properly support the forces generated during the heart cycle. For example, by increasing the foot contact surface area at  414 , the pressure on the tissue adjacent the annulus may be reduced. 
       FIGS. 5A and 5B  are diagrams illustrating various foot angles of anchors and feet, in accordance with embodiments of the subject matter of the disclosure. The foot angles in  FIGS. 5A and 5B  are defined as the angle of the foot with respect to the longitudinal axis of the heart valve prosthesis, as described above. 
       FIG. 5A  is a diagram illustrating a 30 degree foot angle  500  of anchor  502  and foot  504  with respect to the longitudinal axis, indicated at  506 , of the valve, in accordance with embodiments of the subject matter of the disclosure. 
       FIG. 5B  is a diagram illustrating a 0 degree foot angle  510  of anchor  512  and foot  514  with respect to the longitudinal axis, indicated at  516 , of the valve, in accordance with embodiments of the subject matter of the disclosure. Where, the anchor  512  and foot  514  are substantially parallel to the longitudinal axis  516  of the valve. In embodiments, the foot geometry is configured such that the foot angle is within the range of 0 to 45 degrees with respect to the longitudinal axis of the valve. In embodiments, the 0 degree foot angle  510  aligns the foot  514  with the fibrous annulus tissue of the heart valve. 
     In some embodiments, the foot geometry is designed to ensure that the foot contact surface area  414  is such that the maximum pressure exerted by the foot is less than the puncture resistance of the substrate, i.e., the native heart valve tissue contacted by the foot of the prosthesis. Where, the foot geometry and the foot contact surface area  414  are based on multiple items, such as the foot angle, the arc length of the foot, the arc radius of the foot, and the foot width, which can be adjusted to ensure that the maximum pressure exerted by the foot is less than the puncture resistance of the substrate. In addition, the contact surface area  414  can be adjusted or controlled by modifying the profile of the foot at the contact location, as illustrated in  FIG. 6 , which may be a laser cut profile. 
       FIG. 6  is a diagram illustrating embodiments of the profile of a foot, such as the feet  404 ,  504 , and  514 , in accordance with embodiments of the subject matter of the disclosure. As illustrated, iteration A of the foot has a straight width with a maximum width of 0.06 inches, iteration B has a hexagonal shaped, diamond-like structure with a maximum width of 0.12 inches, iteration C has multiple diamond-like structures with a maximum width of 0.216 inches, iteration D has multiple diamond-like structures with a maximum width of 0.13 inches, and iteration E has multiple diamond-like structures with a maximum width of 0.15 inches. 
       FIG. 7  is a diagram illustrating an anchor  600  and a foot  602  having one of the diamond-like structures as depicted in iterations C-E (shown in  FIG. 6 ), in accordance with embodiments of the subject matter of the disclosure. The anchor  600  and the foot  602  are at a foot angle  604  of 0 degrees and the multiple diamond-like structures on the foot  602  provide an increased loading or contact surface area  606 . 
     Also, addition of the diamond-like structures in iterations B-E, as compared to only increasing the strut width, allows for easier formability and manufacturability of these parts as well as improved deliverability. 
       FIG. 8  is a diagram illustrating a native mitral valve  700  and multiple anchor locations  702   a - 702   i  for the feet of a heart valve prosthesis around the circumference of the native mitral valve  700 , in accordance with embodiments of the subject matter of the disclosure. The native mitral valve  700  includes an anterior region  704 , a posterior region  706 , a commissural region  708 , and a medial/lateral region  710 . 
     By adjusting variables including one or more of the locations of the anchors, the number of anchors, the number of feet, the number of feet per anchor, foot angles, foot widths, arc length, and arc radius, the transfer forces and puncture pressures generated by the prosthetic valve may be increased or decreased. Where, in embodiments, a primary function of the foot is to provide stable anchoring to the native heart valve without puncturing into the loading tissue, i.e., the substrate, of the heart. Also, in embodiments, the optimized foot locations in combination with the foot geometry ensure that the foot does not puncture into or through the substrate. 
       FIGS. 9-14  are diagrams illustrating a mitral valve anchoring dock or replacement system that includes a prosthetic heart valve  800  and a delivery system or instrument  802 , in accordance with embodiments of the subject matter of the disclosure. The prosthetic heart valve  800  and the delivery system  802  facilitate an inversion geometry to improve delivery and repositioning/removal of the prosthetic heart valve  800  to and from the native heart valve. 
     In  FIGS. 9-14 , the prosthetic heart valve  800  is shown moving from an expanded configuration in  FIG. 9  through various stages to a collapsed configuration in  FIG. 14 , where the prosthetic heart valve  800  can be delivered to the native annulus. While  FIGS. 9-14  and the accompanying text relate to a certain prosthetic heart valve design, the same general delivery technique may be used with any of a variety of other designs that include anchoring feet, including those designs disclosed in the United States Patent Publications incorporated by reference above. 
       FIG. 9  is a diagram illustrating the delivery system  802  attached to the prosthetic heart valve  800 , i.e., the implant, in the expanded configuration with upward facing anchoring projections  804  having 0 to 45 degree foot angles, in accordance with embodiments of the subject matter of the disclosure. The prosthetic heart valve  800  includes implant arches  806  at the proximal end  808  of the prosthetic heart valve  800 , a hub  810  at the distal end  812  of the prosthetic heart valve  800 , and elongated LV frame members  814  that extend from the hub  810  to the anchoring projections  804  and feet  816  on the anchoring projections  804 . 
     The delivery system  802  includes an outer catheter member  818  attached to the proximal end  808  of the prosthetic heart valve  800  adjacent the heart valve implant arches  806  and an inner catheter member  820  attached to the hub  810  at the distal end  812  of the prosthetic heart valve  800 . In this configuration, the anchoring projections  804  including the feet  816  point upward. In embodiments, the number of anchoring projections  804  and/or elongated LV frame members  814  vary from two to nine. The elongated LV frame member&#39;s length, stiffness, angle relative to the feet  816  and the hub  810 , and curvature facilitate the inversion angle of the feet  816 . In embodiments, the delivery system  802  facilitates inversion of the prosthetic heart valve  800  through a flexible inner catheter member  820  at the hub  810  and a rigid outer catheter member  818  at the implant arches  806 . In embodiments, the outer catheter member  818  is connected to the prosthetic heart valve  800  at other frame locations to further facilitate the inversion geometry. 
       FIG. 10  is a diagram illustrating the delivery system  802  collapsing the prosthetic heart valve  800 , in accordance with embodiments of the subject matter of the disclosure. To collapse the prosthetic heart valve  800 , the inner catheter member  820  is retracted into the outer catheter member  818  and the implant arches  806  collapse against the outer catheter  818 . The inner catheter member  820  attached to the hub  810  is retracted upward through a central opening in the outer catheter member  818  to contain the elongated LV frame members  814  of the prosthetic heart valve  800  within the outer catheter member  818 . 
       FIG. 11  is a diagram illustrating the delivery system  802  further collapsing the prosthetic heart valve  800 , in accordance with embodiments of the subject matter of the disclosure. As shown in  FIG. 11 , the inner catheter member  820  is further retracted into the outer catheter member  818  and the elongated LV frame members  814  are further retracted into the outer catheter  818 . Also, the anchoring projections  804  and the feet  816  pivot outward and progressively downward as the inner catheter member  820  is retracted into the outer catheter  818 . In  FIG. 11 , the anchoring projections  804  and the feet  816  are at a foot angle of about 45 degrees from the longitudinal axis  822  of the prosthetic heart valve  800 . 
       FIG. 12  is a diagram illustrating the delivery system  802  further collapsing the prosthetic heart valve  800 , in accordance with embodiments of the subject matter of the disclosure. As shown in  FIG. 12 , the inner catheter member  820  is further retracted into the outer catheter  818 , the elongated LV frame members  814  are further retracted into the outer catheter  818 , and the anchoring projections  804  and the feet  816  further pivot outward and progressively downward as the inner catheter member  820  is retracted into the outer catheter  818 . In  FIG. 12 , the anchoring projections  804  and the feet  816  are at a foot angle of about 90 degrees from the longitudinal axis  822  of the prosthetic heart valve  800 . 
       FIG. 13  is a diagram illustrating the delivery system  802  further collapsing the prosthetic heart valve  800 , in accordance with embodiments of the subject matter of the disclosure. As shown in  FIG. 13 , the inner catheter member  820  is further retracted into the outer catheter  818 , the elongated LV frame members  814  are further retracted into the outer catheter  818 , and the anchoring projections  804  and the feet  816  further pivot outward and progressively downward as the inner catheter member  820  is retracted into the outer catheter  818 . In  FIG. 13 , the anchoring projections  804  and the feet  816  are at a foot angle of about 150 degrees from the longitudinal axis  822  of the prosthetic heart valve  800 . 
       FIG. 14  is a diagram illustrating the delivery system  802  further collapsing the prosthetic heart valve  800 , in accordance with embodiments of the subject matter of the disclosure. As shown in  FIG. 14 , the inner catheter member  820  is further retracted into the outer catheter  818 , the elongated LV frame members  814  are further retracted into the outer catheter  818 , and the anchoring projections  804  and the feet  816  further pivot outward and progressively downward as the inner catheter member  820  is retracted into the outer catheter  818 . In  FIG. 14 , the anchoring projections  804  and the feet  816  are at a foot angle of about 180 degrees from the longitudinal axis  822  of the prosthetic heart valve  800 . 
     Thus, the anchoring projections  804  and the feet  816  pivot outward and progressively downward from the expanded configuration foot angles of 0 to 45 degrees to the collapsed configuration foot angles of between 45 and 180 degrees as the inner catheter member  820  is retracted into the outer catheter  818 . Once the desired inverted delivery geometry is achieved the inner catheter member  820  is locked in position relative to the outer catheter member  818 . 
       FIG. 15  is a diagram illustrating the inverted state of the prosthetic heart valve  800  in the collapsed configuration and the outer catheter member  818  steered and oriented using other members of the delivery system (not described here) and advanced towards the native mitral valve annulus  824 , in accordance with embodiments of the subject matter of the disclosure. In delivery or readjustment, once the tips of the anchoring projections  804 , i.e., the feet  816 , are sufficiently past the annulus and in good orientation, the inner catheter member  820  is unlocked relative to the outer catheter member  818  and gradually advanced downward, as indicated by the arrow in  FIG. 15 . This releases the hub  810  and the elongated LV frame members  814  of the prosthetic heart valve  800  downward and out of the outer catheter member  818 , which allows the anchoring projections  814  to deploy radially, repositioning until they reach the upward facing expanded configuration and foot angles of 0 to 45 degrees, where they remain post deployment. In this expanded, deployed configuration, the anchoring projections  804  and the feet  816  contact subannular tissue to adequately anchor the prosthetic heart valve  800  at the mitral valve annulus  824 . 
       FIG. 16  is a diagram illustrating the repositioning of the anchoring projections  804  and the feet  816  or the removing of the prosthetic heart valve  800 , where the deployment process described above is reversed, in accordance with embodiments of the subject matter of the disclosure. The inner catheter member  820  attached to the hub  810  is retracted upward through the central opening in the outer catheter member  818 , such as to contain the elongated LV frame members  814  within the outer catheter member  818 . As the elongated LV frame members  814  move inward and into the outer catheter member  818 , the anchoring projections  804  and the feet  816  pivot to an outward and progressively downward position releasing them from the native structures. The outer catheter member  818  can be advanced or retracted further to remove the prosthetic heart valve  800  from the native mitral valve for removal and/or to attempt redelivery. 
     This inverted delivery technique allows for a prosthetic heart valve  800  having a 0 degree foot angle, i.e., a foot oriented generally parallel to the longitudinal axis of the prosthetic heart valve  800 , to be easily delivered. Further, the inverted delivery technique enables reduced delivery depth since the feet  816  are facing forward and only the feet  816  cross the native valve annulus as opposed to each of the hub  810 , the elongated LV frame member  814 , and the implant arches  306  or other components of the prosthetic heart valve  800 . This inverted technique also allows for improved repositioning as the prosthetic heart valve  800  can be retracted into the delivery catheter system  802  to invert back the feet  816  and redeliver the prosthetic heart valve  800 . Further, this technique allows for a reduction in imaging intensity. 
     Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present disclosure. For example, while the embodiments described above refer to particular features, the scope of this disclosure also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present disclosure is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.