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 and radially expandable from the collapsed condition to an expanded condition, the stent extending in a 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 from the inflow end toward the outflow end when the stent is in the expanded condition; and
(c) a cuff including a first wall and a second wall, the second wall being positioned radially outward of the first wall and radially outward of the stent, the second wall being spaced a first distance from the first wall at a plurality of first locations, the first locations being spaced apart from one another around a periphery of the stent, the second wall being spaced a second distance from the first wall at a plurality of second locations, each of the second locations being positioned between adjacent ones of the first locations when the stent is in the expanded condition so that the first and second walls cooperatively define a plurality of openings at the second locations, each said opening facing toward the outflow end and the second distance being greater than the first distance.
2. The prosthetic heart valve of claim 1 , wherein the second wall is attached to the first wall at each of the first locations.
3. The prosthetic heart valve of claim 1 , wherein a multiplicity of the second locations are disposed at a same distance from the inflow end in the longitudinal direction.
4. The prosthetic heart valve of claim 3 , wherein the second locations are disposed at uniform intervals around the periphery of the stent.
5. The prosthetic heart valve of claim 1 , wherein the stent is a unitary balloon-expandable metallic stent.
6. The prosthetic heart valve of claim 5 , wherein the metallic stent is non-woven.
7. The prosthetic heart valve of claim 1 , wherein the stent includes a plurality of struts forming rows of cells, a row of cells adjacent the outflow end forming apices at an outflow edge of the stent.
8. The prosthetic heart valve of claim 1 , wherein an outflow edge of the stent is disposed closer to an edge of the first wall than to the plurality of first locations.
9. The prosthetic heart valve of claim 1 , wherein the stent is cylindrical when in the collapsed condition.
10. A prosthetic heart valve, comprising:
(a) a stent that is radially collapsible to a collapsed condition and radially expandable from the collapsed condition to an expanded condition, the stent extending in a 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 from the inflow end toward the outflow end in the longitudinal 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 being attached to the first wall at a plurality of first locations spaced from the inflow end of the stent, the first locations being spaced apart from one another around a periphery of the stent, the second wall being detached from the first wall at a plurality of second locations, each of the second locations being disposed between adjacent ones of the first locations when the stent is in the expanded condition, the cuff defining openings at the second locations for entry of blood between the first and second walls.
11. The prosthetic heart valve of claim 10 , wherein a multiplicity of the second locations are disposed at a same distance from the inflow end in the longitudinal direction.
12. The prosthetic heart valve of claim 10 , wherein the second locations are disposed at uniform intervals around the periphery of the stent.
13. The prosthetic heart valve of claim 10 , wherein the stent is a unitary balloon-expandable metallic stent.
14. The prosthetic heart valve of claim 13 , wherein the metallic stent is non-woven.
15. The prosthetic heart valve of claim 10 , wherein the stent includes a plurality of struts forming rows of cells, a row of cells adjacent the outflow end forming apices at an outflow edge of the stent.
16. The prosthetic heart valve of claim 10 , wherein an outflow edge of the stent is disposed closer to an edge of the first wall than to the plurality of first locations.
17. The prosthetic heart valve of claim 10 , wherein the stent is cylindrical when in the collapsed condition.