Abstract:
A method and apparatus for facilitating transapical removal of a prosthetic heart valve, i.e., percutaneously implantable valve (PIV), without open-heart surgery. The apparatus includes a holding tool for holding the PIV, a cutting tool for separating the PrV from fibrotic tissue accumulating around the PIV, and a removal tool for extracting the PIV from the heart.

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/965,602, filed Aug. 21, 2007, which is fully incorporated herein by reference. 
    
    
     FIELD OF INVENTION 
     The present invention relates generally to removal of a previously implanted cardiovascular valve, and more particularly to method and apparatus for facilitating removal of a percutaneously implantable valve (PIV) without open-heart surgery. 
     BACKGROUND OF THE INVENTION 
     The demographics of patients suffering valvular disease are broad and the treatment modalities for each are complex. Historically, patients younger than 65 years of age have received mechanical valves, while older patients have received bioprosthetic valves. A new demographic of prosthetic valve recipients has emerged recently, namely, the old, sick, inoperable patient who previously would not be a candidate for surgical implantation of a prosthetic valve. These patients are now candidates for a relatively new type of prosthetic valve, i.e., the percutaneously implantable valve (PIV). The PIV is configured like an endovascular stent, except with a tissue valve sewn in the lumen. Like the endovascular stent, the PIV is balloon expandable or self-expanding, and is delivered by way of a catheter to the operative site, where it is deployed and the delivery system removed. The principal advantage of a PIV is that it avoids open-heart surgery. The old, sick patients who would otherwise not survive open heart surgery, can now benefit from the PIV. 
     Because of a number of design constraints, PIV&#39;s are expected to be less durable and are likely to wear out sooner than conventional, surgically implantable valves. Although PIVs are intended for the old, sick patients who have a relatively short life expectancy, there may be instances in which the patient outlives the functional lifespan of the PIV. Therefore, when the PIV ceases to function, it must be replaced. 
     One potential solution to replacement of a PIV is to insert a new PIV inside the pre-existing PIV. In the field of interventional cardiology, this replacement process is referred to as “restenting.” Restenting a PIV invariably leads to a reduction of effective orifice area of the prosthetic valve, since the old metal cage and worn-out calcified leaflets remain in place and the new PIV is smaller than the pre-existing PIV in order to allow it to be inserted into the remaining lumen. Depending on the original size of the first PIV, and the degree of calcification and obstruction, restenting with another PIV may not lead to an effective orifice area that is compatible with good cardiac function. 
     As indicated above, there may be instances where an old, worn-out PIV will need to be replaced. Currently, the only means of replacing an old, worn-out, fibrosed PIV is through open heart surgery. Since the patient likely received the PIV because they were not a candidate for open-heart surgery and implantation of a conventional bioprosthesis, the patient is unlikely to be a candidate for open heart surgery to replace a worn or failed PIV. Therefore, non-surgical removal of the existing PIV is a preferred option. 
     In view of the issues discussed above, the concept of a system for the removal of an old and/or failed PIV becomes very desirable. The present invention provides a method and apparatus for non-surgical removal of a PIV, and includes a set of tools comprising a valve holding tool, a cutting tool and a valve removal tool that facilitate removal of the PIV through the apex of the heart. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a holding tool for facilitating removal of an implantable cardiovascular valve, the holding tool comprising: a first sliding member; a second sliding member moveable relative to the first sliding member; and a first articulating joint member connected to the first and second sliding members, said articulating joint member moveable between a collapsed position and an expanded position, wherein movement of the second sliding member relative to the first sliding member moves the first articulating joint member between the collapsed and expanded positions. 
     In accordance with another aspect of the present invention, there is provided a cutting tool for facilitating removal of an implantable cardiovascular valve, the cutting tool comprising: a shaft having a longitudinal axis; and a cutting arm extending from the hollow shaft, wherein said cutting arm includes cutting means for cutting tissue. 
     In accordance with still another aspect of the present invention, there is provided a valve removal tool for facilitating removal of an implantable cardiovascular valve from a heart, the valve removal tool comprising: a body; capture means mounted to the body and moveable between a collapsed position and an expanded position, for capturing the implantable cardiovascular valve; and an actuator for actuating movement of the capture means between the collapsed and expanded positions. 
     In accordance with yet another aspect of the present invention, there is provided a method for removing an implantable cardiovascular valve from a heart, the method comprising: holding the cardiovascular valve using a valve holding tool; separating the cardiovascular valve from fibrotic tissue that accumulates adjacent to the cardiovascular valve; and removing the cardiovascular valve from the heart using a valve removal tool, said step of removing including: capturing the cardiovascular valve, and extracting the cardiovascular valve from the heart. 
     An advantage of the present invention is the provision of apparatus for facilitating removal of a percutaneously implantable valve (PIV) from a heart. 
     Another advantage of the present invention is the provision of a valve holding tool, a cutting tool and a valve removal tool for facilitating removal of a percutaneously implantable valve (PIV) from a heart. 
     A still further advantage of the present invention is the provision of a method for facilitating removal of a percutaneously implantable valve (PIV) from a heart. 
     These and other advantages will become apparent from the following description taken together with the accompanying drawings and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention may take physical form in certain parts and arrangement of parts, an embodiment of which will be described in detail in the specification and illustrated in the accompanying drawings which form a part hereof, and wherein: 
         FIG. 1  is a perspective view of a typical PIV shown schematically; 
         FIG. 2  is a schematic diagram showing a PIV deployed inside a native aortic valve; 
         FIG. 3  is a bottom perspective view (inflow aspect) of an aortic root of a heart, including native aortic valve leaflets; 
         FIG. 4  is a partial cut-away view of an aortic root of a heart with a PIV inserted between the native aortic valve leaflets. 
         FIG. 5  is a perspective view of a valve holding tool of the present invention, according to a first embodiment, wherein the valve holding tool is shown in a collapsed position; 
         FIG. 6A  is a plan view of the articulating joint member of the valve holding tool of  FIG. 5 , wherein the valve holding tool is shown in a collapsed position; 
         FIG. 6B  is a plan view of the articulating joint member of the valve holding tool of  FIG. 5 , wherein the valve holding tool is shown in an expanded position; 
         FIG. 7  is a perspective view of a valve holding tool of the present invention, according to a second embodiment, wherein the valve holding tool is shown in an expanded position; 
         FIG. 8  is a plan view of the articulating joint member of the valve holding tool of  FIG. 7 , wherein the valve holding tool is shown in a collapsed position; 
         FIG. 9  is a perspective view of the valve holding tool of  FIG. 7  in the expanded position and engaged with a PIV; 
         FIG. 10  is a perspective view of a cutting tool of the present invention, wherein the cutting tool is shown mounted over a stem portion of the valve holding tool shown in  FIG. 7 ; 
         FIG. 11  is a perspective view showing the valve holding tool of  FIG. 7  engaged with a PIV located inside an aortic valve, and a cutting tool mounted over the stem portion of the valve holding tool; 
         FIG. 12  is a perspective view showing the valve holding tool of  FIG. 7  engaged with a PIV located inside an aortic valve, and a cutting tool mounted over the stem portion of the valve holding tool, the cutting tool having a cutting arm located between the PIV and the native aortic valve leaflets; 
         FIG. 13  is a top plan view of the aortic valve shown in  FIG. 12 , wherein the cutting arm of the cutting tool is located adjacent to the PIV, the cutting tool burning a channel adjacent to the metal cage of the PIV; 
         FIG. 14  is a top plan view of the aortic valve shown in  FIG. 12 , wherein the cutting arm of the cutting tool is located adjacent to the PIV, the cutting tool burning a generally annular-shaped recess along the periphery of the PIV metal cage; 
         FIG. 15  is a schematic diagram showing use of a valve removal tool of the present invention for extracting the PIV from the heart, wherein the valve removal tool is inserted into the heart through the apex after removal of the cutting tool, said removal tool facilitating collapse and extraction of the PIV; 
         FIG. 16  is a partial cross-sectional view of the valve removal tool of  FIG. 15 , shown with articulating arms in an expanded (open) position; 
         FIG. 17  is a perspective view showing the valve holding tool of  FIG. 7  engaged with a PIV located inside the aortic valve, and the valve removal tool of  FIGS. 15 and 16  mounted over a stem portion of the valve holding tool, shown with articulating arms in an expanded (open) position; 
         FIG. 18  is a perspective view of the valve removal tool, shown with articulating arms in a partially collapsed position for capturing the PIV; 
         FIG. 19  is a perspective view of the valve removal tool, shown with articulating arms in a collapsed (closed) position, thereby capturing the PIV; 
         FIG. 20  is a removal tool of the present invention, according to an alternative embodiment, wherein a wire mesh basket is substituted for articulating arms, the removal tool shown in an expanded (open) position; and 
         FIG. 21  is the removal tool of  FIG. 19  shown in a collapsed (closed) position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings wherein the showings are for the purposes of illustrating an embodiment of the invention only and not for the purposes of limiting same,  FIG. 1  shows a typical PIV  10  that may be removed in connection with the present invention. PIV  10  is generally comprised of a flexible, expandable, tubular member  12 , a tubular liner  22  and a plurality of leaflets  26 . As illustrated, tubular member  12  is a mesh cylinder or metal cage formed of intersecting wire sections  14  that define a plurality of openings  16 . Tubular member  12  is radially expandable to contact with tissue, as shown in  FIG. 2 . Liner  22  is formed of tissue or a fabric, such as a woven polyester (e.g., polyethylene terepthalate). Leaflets  26  are typically formed from pericardial tissue, such as bovine or equine pericardium. Alternatively, leaflets  26  may be formed of synthetic materials. It should be appreciated that PIV  10  shown in  FIG. 1  is exemplary of a typical PIV, and is not intended in any way to limit the scope of the present invention. In this respect, it is contemplated that the method and apparatus of the present invention are suitable for use in connection with implantable cardiovascular valves of a wide variety of configurations. 
       FIG. 2  shows a portion of a heart, including aortic root  2 , mitral valve  7  and left ventricle  8 . PIV  10  of  FIG. 1  is shown deployed inside a native aortic valve  4 , wherein PIV  10  is inserted between native valve leaflets  6 .  FIG. 3  is a bottom perspective view (inflow aspect) of aortic root  2  without PIV  10 . In  FIG. 4 , aortic root  2  is shown in detail with PIV  10  installed between aortic valve leaflets  6 . It should be noted that fibrotic tissue (not shown) will accumulate around PIV  10  during the years following implantation. 
     Referring now to  FIGS. 5 ,  6 A and  6 B, there is shown a valve holding tool  40  of the present invention, according to a first embodiment. Holding tool  40  is generally comprised of a first sliding member in the form of an outer tubular body  42 , a second sliding member in the form of an inner rod  52 , and an articulating joint member  80  that is pivotally connected with tubular body  42  and inner rod  52 . Tubular body  42  and inner rod  52  form a stem portion of holding tool  40 . Tubular body  42  defines a cylindrical recess dimensioned to receive rod  52  and has an outer surface dimensioned to receive a detachable handle  60 . One end of rod  52  is connected with tubular body  42  by articulating joint member  80 , while the other end of rod  52  is adapted to receive a detachable handle  70 . 
     With reference to  FIG. 5 , detachable handles  60  and  70  facilitate longitudinally movement of rod  52  relative to tubular body  42  for moving articulating joint member  80  between collapsed and expanded positions, as will be described below. Notches  54  may be respectively formed in tubular body  42  and rod  52  to provide flat surfaces suitable for secure attachment of handles  60  and  70 . 
     Handle  60  includes a pair of pivotally connected arms  62   a  and  62   b . In the illustrated embodiment, a set screw  64  is provided that moves arms  62   a  and  62   b  towards each other when tightened, and moves arms  62   a  and  62   b  away from each other when loosened. Accordingly, arms  62   a  and  62   b  are moved towards each other to capture tubular body  42  between arms  62   a  and  62   b , and thereby detachably engage handle  60  with tubular body  42 . Handle  70  includes a recess  72  that defines a pair of fingers  74   a ,  74   b . Rod  52  is captured between fingers  74   a  and  74   b  to attach handle  70  to rod  52 . 
     It should be appreciated that handles  60  and  70  are exemplary embodiments of suitable detachable handles for use in connection with holding tool  40 , and that the handles may take other suitable forms. Moreover, handle  60  may be substituted for handle  70 , and vice versa. Handles  60  and  70  are configured to be detachable to allow other tools (e.g., cutting and valve removal tools) to conveniently slide over the stem portion of holding tool  40 , as will be described below. 
     Articulating joint member  80  is comprised of a plurality of articulating legs  84 . Each articulating leg  84  includes first and second leg sections  86  and  88  that are pivotally connected to each other at a hub member  90 . First leg section  86  is pivotally connected at one end with tubular body  42  and second leg section  88  is pivotally connected at one end with rod  52 . Each hub member  90  includes a projection  92  dimensioned to engage with tubular member  12  of PIV  10 . In the illustrated embodiment, projection  92  takes the form of an outward extending hook  92 . It is contemplated that projection  92  may take other suitable forms. 
     As rod  52  is moved relative to tubular body  42 , articulating joint member  80  moves between a collapsed position ( FIGS. 5 and 6A ) and an expanded position ( FIG. 6B ). In the expanded position, projections  92  can grasp wire sections  14  of tubular member  12  and/or hook onto liner  22 , thereby engaging holding tool  40  with PIV  10 . 
     It should be appreciated that the angular geometry of articulating joint member  80  allows projections  92  to exert significant outward force against tubular member  12  and/or liner  22  of PIV  10 , when articulating joint member  80  is moved to the expanded position. Accordingly, a surgeon removing PIV  10  can conveniently grasp holding tool  40  with one hand, thereby stabilizing the heart and PIV  10 , while manipulating cutting tool  120  around PIV  10 , as will be described below. 
       FIGS. 7 and 8  illustrate a holding tool  40 A of the present invention, according to a second embodiment. Holding tool  40 A includes a first sliding member in the form of an outer tubular body  102 , a second sliding member in the form of an inner tubular body  104 , a third sliding member in the form of an inner tubular body  106 , a fourth sliding member in the form of an inner rod  108 , and a pair of articulating joint members  80 A and  80 B. In this embodiment, outer tubular body  102 , inner tubular body  104 , inner tubular body  106 , and inner rod  108  form a stem portion of holding tool  40 A, wherein inner tubular body  104  extends through outer tubular body  102 , inner tubular body  106  extends through inner tubular body  104 , and inner rod  108  extends through inner tubular body  106 . 
     Articulating joint members  80 A and  80 B are essentially the same as articulating joint member  80  described above. Thus, like components are given the same reference numbers. Articulating joint member  80 A is pivotally connected with tubular body  102  and inner tubular body  104 . Similarly, articulating joint member  80 B is pivotally connected with inner tubular body  106  and inner rod  108 . Notches  54 A dimensioned to receive detachable handles are respectively formed in outer tubular body  102 , inner tubular body  104 , inner tubular body  106 , and inner rod  108 . The detachable handles may take the form of handles  60  or  70  described above. 
     As inner tubular body  104  is moved relative to tubular body  102 , articulating joint member  80 A moves between a collapsed position ( FIG. 8 ) and an expanded position ( FIG. 7 ). Likewise, as inner rod  108  is moved relative to inner tubular body  106 , articulating joint member  80 B moves between a collapsed position ( FIG. 8 ) and an expanded position ( FIG. 7 ). In the expanded position, projections  92  of articulating joint members  80 A,  80 B grasp wire sections  14  of tubular member  12  and/or hook onto liner  22 , thereby engaging holding tool  40 A with PIV  10 .  FIG. 9  illustrates holding tool  40 A in engagement with PIV  10 . 
     It should be appreciated that holding tools  40 ,  40 A not only serve the function of holding PIV  10 , but also act as a guide to locate the cutting and valve removal tools relative to PIV  10 . 
     Referring now to  FIGS. 10 and 11 , there is shown a cutting tool  120  according to the present invention. In the figures, cutting tool  120  is shown mounted over the stem portion of holding tool  40 A. It should be appreciated that holding tool  40  may be substituted for holding tool  40 A. Cutting tool  120  is generally comprised of a hollow shaft  122 , a handle portion  126  extending from a first end of shaft  122 , and an L-shaped cutting arm  130  extending from a second end of shaft  122 . 
     Shaft  122  includes a cylindrical recess dimensioned to receive the stem portion of holding tool  40 A. In this respect, shaft  122  is slidable over the stem portion of holding tool  40 A, when all handles are detached therefrom. Handle portion  126  provides a surface for gripping and maneuvering cutting tool  120 . 
     Arm  130  includes an elongated portion  131  that is generally parallel to the longitudinal axis of shaft  122 . A plurality of axially-mounted fiber optic guides  132  and a plurality of transverse-mounted fiber optic guides  134  are mounted to elongated portion  131  of arm  130 . Internal channels (not shown), formed within handle portion  126 , shaft  122  and arm  130 , are dimensioned to receive fiber optic cable  142 . Fiber optic cable  142  connects fiber optic guides  132 ,  134  to a source of laser energy (not shown). Accordingly, laser energy is transmitted to fiber optic guides  132 ,  134  via fiber optic cable  142 . Fiber optic guides  132  emit laser beams in a direction generally parallel to the longitudinal axis of shaft  122 , while fiber optic guides  134  emit laser beams in a direction transverse to the longitudinal axis of shaft  122 . Accordingly, fiber optic guides  132  are appropriately positioned to cut (i.e., burn) a channel adjacent to PIV  10  ( FIGS. 12 and 13 ), and fiber optic guides  134  are appropriately positioned to cut (i.e., burn) a generally annular recess around the periphery of PIV  10  ( FIG. 14 ). 
     In  FIGS. 10-14 , cutting tool  120  is shown in conjunction with holding tool  40 A for the purpose of illustrating operation of cutting tool  120 . However, it should be appreciated that holding tool  40  may be substituted for holding tool  40 A. 
     It is contemplated that other suitable cutting means may be substituted for the laser-based cutting means comprised of fiber optic guides, fiber optic cable and a laser energy source. For example, the cutting tool may include cutting means in the form of a mechanical cutting device, such as a conventional mechanical oscillating cutting blade, or an electrosurgical cutting device. A conventional electrosurgical cutting device includes electrode(s) for applying a high frequency, high voltage to tissue. It is further contemplated that the cutting tool may include a combination of different types of cutting means. 
     The operation of cutting tool  120  will now be described detail with reference to  FIGS. 11-14 . After holding tool  40 A is properly engaged with PIV  10  (as described above), handles  60  and  70  are removed from holding tool  40 A. Cutting tool  120  is then mounted over the stem portion of holding tool  40 A, as shown in  FIG. 11 . Cutting tool  120  is slid along the stem portion while fiber optic guides  132  are energized to emit laser beams in an axial direction. Accordingly, a channel is burned adjacent to PIV  10 , as shown in  FIGS. 12 and 13 . Thereafter, cutting tool  120  is rotated circumferentially while fiber optic guides  134  are energized to emit laser beams in a transverse direction. Accordingly, a generally annular recess is formed around the periphery of PIV  10 , as shown in  FIG. 14 . Handle portion  126  is used to move and rotate cutting tool  120  relative to PIV  10 . The cutting of the channel and a complete annular recess using cutting tool  120  is necessary to separate PIV  10  from fibrotic tissue that accumulates adjacent to PIV  10 . After PIV  10  is separated from fibrotic tissue, cutting tool  120  is removed by dismounting it from the stem portion of holding tool  40 A. PIV  10  is stabilized by grasping the stem portion of holding tool  40 . Handles  60 ,  70  may be re-attached to the stem portion after mounting cutting tool  120 . 
       FIG. 15  schematically illustrates a valve removal tool  150 , according to a first embodiment. After removal of cutting tool  120 , valve removal tool  150  is slid over the stem portion of holding tool  40 A and inserted into the heart through the apex. Operation of removal tool  150  will be described in detail below. 
     Removal tool  150  will now be described in detail with reference to  FIG. 16 . Removal tool  150  resembles a trocar, and is generally comprised of a hollow cylindrical body  152 , a plurality of articulating arms  180 , a cylindrical inner sleeve  202 , a plurality of links  212  for connecting arms  180  to inner sleeve  202 , and an actuator  170  for controlling movement of arms  180 . 
     Inner sleeve  202  is located inside a cylindrical recess  153  of cylindrical body  152 . Axial movement of inner sleeve  202  within cylindrical body  152  results in movement of arms  180  between a collapsed (closed) position ( FIGS. 15 and 19 ) and an expanded (open) position ( FIG. 16 ). Inner sleeve  202  is connected with arms  180  via links  212 . The first end  214  of link  212  has a ball hinge that is dimensioned to be received by a generally spherical cavity  204  formed in inner sleeve  202 . The second end  216  of link  212  is pivotally connected to arm  180 . Link  212  extends through a slot  166  in cylindrical body  152  to connect with inner sleeve  202 . Inner sleeve  202  also includes a slot  205  and a pin  206 . Pin  206  extends across slot  205  to operatively connect inner sleeve  202  with actuator  170 . A generally cylindrical recess  203  is defined by inner sleeve  202 . 
     A bracket member  154  extends outward from the outer surface of cylindrical body  152 . Bracket member  154  supports actuator  170  that is pivotally attached to bracket member  154  by a pivot pin  156 . Actuator  170  includes fingers  172  that extend through a slot  158  formed in body  152 . Fingers  172  capture pin  206  of inner sleeve  202 . Rotation of actuator  170  causes axial movement of inner sleeve  202 , thereby moving arms  180  between the collapsed and expanded position. In the illustrated embodiment, actuator  170  resembles a scissors handle. 
     Each arm  180  includes a curved elongated section  182 , and an inward facing conical portion  184 . A curved notch  186  is formed at the distal end of conical portion  184 . When arms  180  are in the collapsed position, curved notches  186  define an opening  188 . Opening  188  and cylindrical recesses  153 ,  203  have diameters dimensioned to receive the stem portion of holding tools  40 ,  40 A (see  FIG. 15 ). Each arm  180  also includes a slot  196  dimensioned to receive a portion of link  212 . 
     The operation of removal tool  150  will now be described with reference to FIGS.  15  and  17 - 19 . Arms  180  are moved to a collapsed position and removal tool  150  is mounted over the stem portion of holding tool  40 A. Removal tool  150  is inserted into the heart through the apex ( FIG. 15 ) and moved toward PIV  10 . As removal tool  150  approaches PIV  10 , arms  180  are moved to the expanded position ( FIG. 17 ). Removal tool  150  is then moved to a position relative to PIV  10  such that arms  180  can capture PIV  10  as arms  180  are moved towards collapsed position, as shown in  FIG. 18 . As arms  180  move to the collapsed position they exert a force on tubular member  12  of PIV  10 , thereby causing tubular member  12  to collapse. In the illustrated embodiment, PIV  10  is fully captured within arms  180  when arms  180  are in the fully collapsed position shown in  FIG. 19 . The PIV  10  is then removed from the heart by simultaneously withdrawing both holding tool  40 A and removal tool  150  from the heart, as illustrated in  FIG. 19 . 
     Referring now to  FIGS. 20 and 21 , there is shown a removal tool  150 A of the present invention, according to a second embodiment. Removal tool  150 A includes some of the same components as removal tool  150 , and such components are labeled with the same reference numbers. 
     Removal tool  150 A is generally comprised of a cylindrical body  152 A, a cylindrical inner sleeve  202 A located within a cylindrical recess  153 A defined by cylindrical body  152 A, and a conically-shaped wire mesh basket  220 . A pivoting arm  226  extends outward from one end cylindrical body  152 A. Inner sleeve  202 A defines a cylindrical recess  203 A. 
     Wire mesh basket  220  is mounted to one end of cylindrical body  152 A. Wire mesh basket  220  includes a wire cable  222  that extends through a hole formed in pivoting arm  226  and connects with inner sleeve  202 A. Basket  220  is dimensioned to receive PIV  10  when basket  220  is in an expanded (open) position, as shown in  FIG. 20 . 
     A bracket member  154  extends outward from the outer surface of cylindrical body  152 A. Bracket member  154  supports actuator  170  that is pivotally attached to bracket member  154  by a pivot pin  156 . Actuator  170  includes fingers  172  that extend through a slot  158  formed in body  152 A. Fingers  172  capture pin  206  of inner sleeve  202 A. Rotation of actuator  170  causes axial movement of inner sleeve  202 A, thereby causing movement of wire cable  222 . Application of tension to wire cable  222  moves wire mesh basket  220  from an expanded (open) position ( FIG. 20 ) to a collapsed (closed) position ( FIG. 21 ). 
     Removal tool  150 A operates in a similar manner as removal tool  150  to extract PIV  10  from a heart. In this respect, removal tool  150 A is adapted to be mounted over the stem portion of a holding tool, and located proximate to a PIV  10 . Wire mesh basket  220  is moved between an expanded position and a collapsed position to capture and extract PIV  10 . 
     The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purposes of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. For instance, it is contemplated by the inventor that the present invention may find utility with implantable cardiovascular valves other than PIVs. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.