Apparatus and methods for replacing a cardiac valve

Abstract

An apparatus and method for replacing a cardiac valve includes an expandable support member having oppositely disposed first and second ends, a main body portion extending between the ends, and a prosthetic valve within the main body portion. The main body portion has an annular shape for expanding into position in the annulus of the valve. The first and second ends include a plurality of upper and lower wing members movable from a collapsed condition into an extended condition for respectively engaging a first section of cardiac tissue surrounding the valve and for engaging a portion of the native valve leaflets to pin the leaflets back against the annulus. The second end further includes at least two strut members spaced apart from each other. A respective one of the strut members is attached to at least one commissural section of the prosthetic valve to prevent prolapse of the valve leaflets.

1 . An apparatus for replacing a cardiac valve having at least two native valve leaflets, said apparatus comprising: 
 an expandable support member having oppositely disposed first and second ends and a main body portion extending between said ends, said main body portion of said support member having an annular shape for expanding into position in the annulus of the cardiac valve;    said first end of said support member comprising a plurality of upper wing members that extend from said main body portion, each of said upper wing members being movable from a radially collapsed condition into a radially extended condition for engaging a first section of cardiac tissue surrounding one-side of the cardiac valve;    said second end of said support member comprising a plurality of lower wing members that extend from said main body portion, each of said lower wing members being movable from a radially collapsed condition into a radially extended condition for engaging a portion of the native valve leaflets to pin the leaflets back against the annulus of the native cardiac valve;    said second end of said support member further including at least two strut members that are spaced apart from each other; and    a prosthetic valve secured within said main body portion of said support member, said prosthetic valve having at least two valve leaflets that are coaptable to permit unidirectional flow of blood, each of said at least two valve leaflets being joined together at at least two commissural sections that are spaced apart from each other, each of said at least two commissural sections being attached to a respective one of said strut members to prevent prolapse of said valve leaflets.    
   
   
       2 . The apparatus of  claim 1  wherein said plurality of upper wing members, in their radially extended condition, extend transverse to the direction of blood flow through said prosthetic valve.  
   
   
       3 . The apparatus of  claim 1  wherein at least one of said plurality of upper wing members includes at least one attachment mechanism for embedding into the first section of cardiac tissue to help secure said support member in the annulus of the cardiac valve.  
   
   
       4 . The apparatus of  claim 3  wherein said at least one attachment mechanism includes at least one barb.  
   
   
       5 . The apparatus of  claim 1  wherein at least one of said plurality of lower wing members includes at least one attachment mechanism for embedding into a portion of the native valve leaflets to help secure said support member in the annulus of the cardiac valve.  
   
   
       6 . The apparatus of  claim 1  wherein said main body portion has a concave cross-sectional shape for conforming to the convex shape of the annulus of the cardiac valve.  
   
   
       7 . The apparatus of  claim 1  wherein said plurality of lower wing members includes first and second lower wing members for positioning at the commissures of the native cardiac valve.  
   
   
       8 . The apparatus of  claim 7  wherein said first and second lower wing members are spaced approximately 180° apart.  
   
   
       9 . The apparatus of  claim 8  wherein said plurality of lower wing members further includes third and fourth lower wing members for positioning directly over respective central portions of the at least two native valve leaflets.  
   
   
       10 . The apparatus of  claim 9  wherein said third and fourth lower wing members are spaced approximately 180° apart and are located in-between said first and second lower wing members, respectively.  
   
   
       11 . The apparatus of  claim 1  wherein said plurality of lower wing members includes a first group of lower wing members for positioning at the commissures of the native cardiac valve.  
   
   
       12 . The apparatus of  claim 11  wherein said plurality of lower wing members further includes a second group of lower wing members for positioning directly over respective central portions of the at least two native valve leaflets, said first and second groups of lower wing members being arranged in an alternating fashion.  
   
   
       13 . The apparatus of  claim 1  wherein said plurality of lower wing members includes at least two lower wing members for positioning directly over respective central portions of the at least two native valve leaflets.  
   
   
       14 . The apparatus of  claim 1  further comprising a layer of biocompatible material covering at least a portion of said support member.  
   
   
       15 . The apparatus of  claim 1  wherein at least a portion of said support member is treated with at least one therapeutic agent for eluting into cardiac tissue.  
   
   
       16 . The apparatus of  claim 1  wherein a plurality of portions of said support member are separately treated with a different therapeutic agent.  
   
   
       17 . A method for replacing a cardiac valve having at least two native valve leaflets, said method comprising the steps of: 
 providing a prosthetic valve that includes an expandable support member having oppositely disposed first and second ends and a main body portion extending between the ends, a plurality of upper wing members that extend from a one end of the main body portion, and a plurality of lower wing members that extend from an opposite end of the main body portion, the second end of the support member further including at least two strut members, the prosthetic valve having at least two valve leaflets that are joined together at at least two commissural sections, each of the at least two commissural sections being attached to a respective one of the strut members to prevent prolapse of the valve leaflets;    placing the main body portion of the prosthetic valve within the annulus of the cardiac valve to be replaced;    expanding the main body portion into engagement with the annulus of the cardiac valve to secure the prosthetic valve in the annulus;    deploying the upper wing members from a radially collapsed condition into a radially extended condition into engagement with a first section of cardiac tissue surrounding one side of the cardiac valve; and    deploying the lower wing members from a radially collapsed condition into a radially extended condition into engagement with a portion of the native valve leaflets to pin the leaflets back against the annulus of the native cardiac valve.    
   
   
       18 . The method of  claim 17  wherein said step of placing the main body portion of the prosthetic valve within the annulus of the cardiac valve to be replaced further comprises the steps of: 
 placing the support member around an inflatable balloon in a secured manner;    inserting the balloon and support member into an atrial chamber;    advancing the balloon until the support member is positioned within the annulus of the cardiac valve to be replaced; and    expanding the support member with the balloon so that the support member engages the annulus of the cardiac valve to secure the support member in the annulus.    
   
   
       19 . The method of  claim 18  wherein the balloon has an hourglass shape defined by first and second bulb sections connected by a center section having a smaller diameter than the bulb sections, said step of placing the support member around the balloon further comprising the step of positioning the support member about the center section.  
   
   
       20 . The method of  claim 19  wherein said step of advancing the balloon until the support member is positioned within the valve annulus further includes the step of positioning the first bulb section within the leaflets of the native valve so that when the balloon is inflated the first bulb pushes the valve leaflets back to protect the leaflets during expansion of the support member.  
   
   
       21 . The method of  claim 18  wherein said step of expanding the support member with the balloon so that the support member engages the annulus of the cardiac valve includes the step of conforming the main body portion to the shape of the valve annulus to help locate and secure the support member in the valve annulus by radially forcing the main body portion into the valve annulus.  
   
   
       22 . The method of  claim 17  wherein each of the plurality of wing members include at least one attachment mechanism for embedding into cardiac tissue.  
   
   
       23 . The method of  claim 22  wherein the attachment mechanism includes at least one barb extending from each of the wing members, said method further including the step of embedding the at least one barb into cardiac tissue to further secure the support member in the valve annulus.  
   
   
       24 . The method of  claim 23  wherein each of the wing members has a concave cross-sectional shape for conforming to the convex shape of the valve annulus, said method further comprising the step of pulling the wing members into a flatter cross-sectional shape with a constraining wire for placement of the support member, the at least one barb extending generally radially when the wing members are being held by the constraining wire.  
   
   
       25 . The method of  claim 24  further comprising the step of releasing the constraining wire after said step of expanding the support member with the balloon so that the upper wing members spring radially outward to engage the first section of cardiac tissue, and the lower wing members spring radially outward to engage a portion of the native valve leaflets.  
   
   
       26 . The method of  claim 25  wherein said step of releasing the constraining wire causes the at least one barb to embed into cardiac tissue in the distal direction.  
   
   
       27 . The method of  claim 17  wherein said step of inserting the balloon and the prosthetic valve into the heart chamber is done percutaneously via an intravascular catheter.  
   
   
       28 . The method of  claim 27  wherein said step of inserting the balloon and the prosthetic valve into the heart chamber is done via a minimally invasive approach.  
   
   
       29 . The method of  claim 27  wherein said step of inserting the balloon and the prosthetic valve into the heart chamber is done via an open-chest procedure.  
   
   
       30 . The method of  claim 17  wherein at least a portion of the support member is treated with at least one therapeutic agent for eluting into cardiac tissue, the method further comprising the step of allowing the at least one therapeutic agent to elute into the cardiac tissue.