Collapsible and re-expandable prosthetic heart valve cuff designs and complementary technological applications
A prosthetic heart valve is provided with a cuff having features which promote sealing with the native tissues even where the native tissues are irregular. The cuff may include a portion adapted to bear on the LVOT when the valve is implanted in a native aortic valve. The valve may include elements for biasing the cuff outwardly with respect to the stent body when the stent body is in an expanded condition. The cuff may have portions of different thickness distributed around the circumference of the valve in a pattern matching the shape of the opening defined by the native tissue. All or part of the cuff may be movable relative to the stent during implantation.
1. A prosthetic heart valve, comprising:
(a) a stent that is radially collapsible to a collapsed condition for mounting on a delivery device and is radially expansible from the collapsed condition to an expanded condition when the stent is implanted, the stent extending in a longitudinal direction between an inflow end and an outflow end;
(b) a valve element mounted within the stent, the valve element being collapsible and expandable along with the stent, the valve element being arranged to allow flow of blood within the stent towards the outflow end when the stent is in the expanded condition; and
(c) a cuff including a first wall and a second wall radially outward of the first wall and radially outward of the stent, the first and second walls cooperatively defining at least one pocket and at least one opening for entry of blood into the at least one pocket when the stent is in the expanded condition, the at least one opening being disposed adjacent the inflow end of the stent, the at least one opening facing toward the outflow end of the stent so that when the stent is implanted, retrograde blood flow around the outside of the stent can bias the second wall outwardly into engagement with native tissue.
2. The prosthetic heart valve according to claim 1 wherein the first wall extends beyond the second wall in a distal direction toward the outflow end of the stent.
3. The prosthetic heart valve according to claim 1 wherein the at least one opening includes a plurality of openings.
4. The prosthetic heart valve according to claim 3 wherein all of the plurality of openings are disposed at the same location in the longitudinal direction.
5. The prosthetic heart valve according to claim 3 wherein the plurality of openings are disposed at uniform intervals around the periphery of the stent.
6. The prosthetic heart valve according to claim 3 , wherein the at least one pocket includes a plurality of pockets.
7. The prosthetic heart valve according to claim 6 wherein the pockets are separated from one another by substantially closed sides.
8. The prosthetic heart valve according to claim 1 wherein the stent includes an annulus section adjacent the inflow end, the annulus section being adapted to engage native tissue adjacent an annulus of a native valve, and wherein second wall of the cuff is disposed around the annulus section of the stent.
9. The prosthetic heart valve according to claim 8 wherein the valve element is at least partially disposed within the annulus section.
10. The prosthetic heart valve according to claim 1 , wherein the stent is self-expanding.
11. The prosthetic heart valve according to claim 1 , wherein the stent is balloon-expandable.
12. A prosthetic heart valve, comprising:
(a) a stent that is radially collapsible to a collapsed condition for mounting on a delivery device and radially expansible from the collapsed condition to an expanded condition when the stent is implanted, the stent extending in a distal longitudinal direction from an inflow end to an outflow end;
(b) a valve element mounted within the stent, the valve element being collapsible and expandable along with the stent, the valve element being arranged to allow flow of blood in the distal direction when the stent is in the expanded condition; and
(c) a cuff including a first wall and a second wall radially outward of the first wall and radially outward of the stent, the second wall having a distal edge, the distal edge of the second wall being in proximity to the first wall at a plurality of first locations spaced apart from one another around the periphery of the stent and radially spaced apart from the first wall at least one second location disposed between the first locations when the stent is in the expanded configuration so that the first and second walls cooperatively define at least one opening at the at least one second location, each said opening facing toward the outflow end for entry of blood between the first and second walls to bias the second wall of the cuff outwardly into engagement with native tissue.
13. The prosthetic heart valve according to claim 12 wherein the at least one second location includes a plurality of second locations interspersed with the first locations around the periphery of the stent.
14. The prosthetic heart valve according to claim 13 wherein all of the second locations are disposed at the same location in the distal longitudinal direction.
15. The prosthetic heart valve according to claim 14 wherein the second locations are disposed at uniform intervals around the periphery of the stent.
16. The prosthetic heart valve according to claim 12 wherein the stent includes an annulus section adjacent the inflow end, the annulus section being adapted to engage native tissue adjacent an annulus of a native valve, and wherein the second wall of the cuff is disposed around the annulus section of the stent.
17. The prosthetic heart valve according to claim 16 wherein the valve element is at least partially disposed within the annulus section.
18. The prosthetic heart valve according to claim 12 wherein the edge of the second wall is attached to the first wall at the first locations.
19. The prosthetic heart valve according to claim 12 wherein the first wall extends distally beyond the second wall.
20. The prosthetic heart valve according to claim 12 , wherein the stent is self-expanding.
21. The prosthetic heart valve according to claim 12 , wherein the stent is balloon-expandable.