Collapsible and re-expandable prosthetic heart valve cuff designs and complementary technological applications
A prosthetic heart valve includes (a) a stent body including a generally tubular annulus region having a tubular wall and a proximal-to-distal axis, the stent body having a radially expanded condition when the stent body is implanted, (b one or more prosthetic valve elements mounted to the stent body and operative to allow blood flow in a distal direction through the annulus region but to substantially block blood flow in a proximal direction through the annulus region, (c) a cuff coupled to the stent body, and (d) one or more biasing elements connected to the stent body and to the cuff, the biasing elements being adapted to bias at least a portion of the cuff outwardly with respect to the stent body.
1. A prosthetic heart valve, comprising:
(a) a stent body including a tubular annulus region having a tubular wall and a proximal-to-distal axis, the stent body having a radially expanded condition when the stent body is implanted, the stent body having a plurality of cells;
(b) one or more prosthetic valve elements mounted to the stent body and operative to allow blood flow in a distal direction through the annulus region but to substantially block blood flow in a proximal direction through the annulus region;
(c) a cuff having a proximal edge and a distal edge and being configured to cover at least some of the plurality of cells, the cuff being coupled to, and lining, the stent body from the proximal edge to the distal edge; and
(d) one or more biasing elements engaged with the stent body and the cuff, the one or more biasing elements being adapted to bias at least a portion of the cuff outwardly with respect to the stent body without piercing the cuff in the radially expanded condition when the stent body is implanted.
2. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements include springs.
3. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements are integrally and unitarily formed with the stent body.
4. The prosthetic heart valve of claim 1 , wherein, in the radially expanded condition, the one or more biasing elements project outwardly from the tubular wall of the annulus region.
5. The prosthetic heart valve of claim 1 , wherein the cuff is disposed outward of the tubular wall of the annulus region.
6. The prosthetic heart valve of claim 1 , wherein the cuff includes an outermost layer disposed outward of the tubular wall of the annulus region.
7. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements terminate in blunt ends.
8. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements bear on a juncture between struts of the stent body.
9. The prosthetic heart valve of claim 1 , wherein the cuff comprises a multi-layer cuff and the one or more biasing elements are provided between layers of the multi-layer cuff.
10. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements comprise a shape-memory material.
11. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements comprise Nitinol.
12. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements match a curvature of the stent body when the stent body is in a radially collapsed condition.
13. The prosthetic heart valve of claim 1 , wherein the one or more biasing elements are heat set.
14. The prosthetic heart valve of claim 1 , wherein the cuff is positioned radially outward of the stent body such that blood flow in the proximal direction around an outside of the stent body provides an outward bias to portions of the cuff, to promote effective sealing between the cuff and surrounding native tissue.
15. A prosthetic heart valve, comprising:
(a) a stent body including an aortic region and an annulus region having a tubular wall and a proximal-to-distal axis, the stent body having a radially expanded condition when the stent body is implanted, and a radially collapsed condition, the stent body having a plurality of cells;
(b) one or more prosthetic valve elements mounted to the stent body and operative to allow blood flow in a distal direction through the annulus region but to substantially block blood flow in a proximal direction through the annulus region;
(c) a cuff having a proximal edge and a distal edge and being configured to cover at least some of the plurality of cells, the cuff being coupled to, and lining, the stent body from the proximal edge to the distal edge; and
(d) one or more biasing elements connected to the stent body adjacent the annulus region and extending toward the aortic region, the one or more biasing elements being adapted to bias at least a portion of the cuff outwardly with respect to the stent body in the radially expanded condition, the one or more biasing elements being entirely disposed radially inward of the cuff in both the radially collapsed condition and radially expanded condition when the stent body is implanted.
16. The prosthetic heart valve of claim 15 , wherein the cuff is positioned radially outward of the stent body such that blood flow in the proximal direction around an outside of the stent body provides an outward bias to portions of the cuff, to promote effective sealing between the cuff and surrounding native tissue.
17. The prosthetic heart valve of claim 15 , wherein the one or more biasing elements comprise a plurality of biasing elements circumferentially disposed about the stent body.
18. The prosthetic heart valve of claim 15 , wherein the one or more biasing elements are integrally formed with the stent body.
19. The prosthetic heart valve of claim 15 , wherein the stent body includes a plurality of cells and the one or more biasing elements are joined to apices of ones of the plurality of cells.
20. The prosthetic heart valve of claim 15 , wherein the one or more biasing elements are positioned to be nested between struts in the radially collapsed condition.