DEVICE AND METHOD FOR REPLACING MITRAL VALVE
A prosthetic mitral valve assembly is disclosed. The assembly comprises a radially-expandable stent including a lower portion sized for deployment between leaflets of a native mitral valve and an upper portion having a flared end. The upper portion is sized for deployment within the annulus of the mitral valve and the flared end is configured to extend above the annulus. The stent is formed with a substantially D-shape cross-section for conforming to the native mitral valve. The D-shape cross-section includes a substantially straight portion for extending along an anterior side of the native mitral valve and a substantially curved portion for extending along a posterior side of the native mitral valve. The assembly further includes a valve portion formed of pericardial tissue and mounted within an interior portion of the stent for occluding blood flow in one direction.
1 . A prosthetic mitral valve assembly, comprising:
a radially-expandable stent including a lower portion sized to held between leaflets of a native mitral valve and an upper portion having a flared end, the upper portion sized for deployment within the annulus of the mitral valve with a pressure fit, the flared end configured to extend above the annulus, wherein the stent tapers from the upper portion to the lower portion, the stent having a substantially D-shape cross-section for conforming to the native mitral valve, the D-shape cross-section providing a substantially straight portion configured to extend along an anterior side of the native mitral valve and a substantially curved portion configured to extend along a posterior side of the native mitral valve; and
a valve portion formed of pericardial tissue and mounted within an interior portion of the stent, the valve portion having leaflets for occluding blood flow in one direction and replacing the function of the native mitral valve.
2 . The prosthetic mitral valve assembly of claim 1 , wherein the stent is made of nitinol.
3 . The prosthetic mitral valve assembly of claim 1 , wherein the valve portion comprises three leaflets.
4 . The prosthetic mitral valve assembly of claim 1 , wherein the valve portion is a bicuspid valve having only two leaflets.
5 . The prosthetic mitral valve assembly of claim 4 , wherein the two leaflets differ in size.
6 . The prosthetic mitral valve assembly of claim 1 , wherein the stent is formed with intercrossing bars.
7 . The prosthetic mitral valve assembly of claim 1 , further including tension members extending between the leaflets and the stent.
8 . The prosthetic mitral valve assembly of claim 7 , wherein the tension members are coupled at different heights, relative to one another, along a length of the stent.
9 . The prosthetic mitral valve assembly of claim 1 , wherein the stent has a truncated conical shape.
10 . The prosthetic mitral valve assembly of claim 1 , wherein the flared end is scalloped.
11 . The prosthetic mitral valve assembly of claim 1 , wherein the prosthetic mitral valve assembly is held in place without clamping onto tissue.
12 . The prosthetic mitral valve assembly of claim 1 , wherein the stent includes external prongs to assist in holding the prosthetic mitral valve assembly in place.
13 . The prosthetic mitral valve assembly of claim 1 , wherein the stent and the valve portion are collapsible to a reduced diameter for insertion into the heart on a delivery catheter for implantation.
14 . The prosthetic mitral valve assembly of claim 1 , further including a tether coupled to the stent on one end thereof, the tether being configured to couple the stent to a portion of the heart remote from the stent.
15 . The prosthetic mitral valve assembly of claim 1 , wherein the valve portion further includes tension members coupled to the prosthetic leaflets for preventing the prosthetic leaflets from everting and reducing stresses induced by ventricular contraction.
16 . The prosthetic mitral valve assembly of claim 15 , wherein the tension members are coupled to the prosthetic leaflets at a first end of the tension members and coupled at an opposite end to the stent or to a patient's heart.
17 . The prosthetic mitral valve assembly of claim 15 , wherein the tension members are coupled to the stent at a first end of the tension members and coupled at an opposite end to a portion of the patient's heart.