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 for replacement of a native heart valve having a native valve annulus, comprising:
a stent body having a proximal end adjacent an inflow end and a distal end adjacent an outflow end and including an annulus section and a flared region proximal to the annulus section, the stent body having a radially collapsed condition and a radially expanded condition, the annulus section and the flared region increasing in diameter during transition from the radially collapsed condition to the radially expanded condition, the flared region extending from the annulus section to the proximal end of the stent, wherein the stent body further includes an aortic section distal to the annulus section;
one or more prosthetic valve elements mounted to the stent body and operative to allow flow in an antegrade direction from the inflow end to the outflow end but to substantially block flow in a retrograde direction from the outflow end to the inflow end; and
a cuff secured to the stent body, the cuff including an outer cuff portion and an inner cuff portion, the outer cuff portion covering an exterior surface of the flared region, the inner cuff covering an interior surface of the flared region, the outer cuff portion defining a ring having a main portion that projects radially outward farther than any portion of the annulus section of the stent body, and a proximal edge axially offset from the main portion,
wherein the outer cuff portion, in cooperation with the proximal edge of the ring, is adapted for engagement with native tissue proximal to the native valve annulus to form a seal with the native tissue to block retrograde flow around an exterior surface of the stent body.
2. The prosthetic heart valve of claim 1 , wherein the stent body includes a concave curvature extending between the aortic section and the flared region.
3. The prosthetic heart valve of claim 1 , wherein the inner cuff portion includes a supra-annular cuff portion positioned adjacent the annulus section and a sub-annular cuff portion positioned proximal to the supra-annular cuff portion.
4. The prosthetic heart valve of claim 3 , wherein the sub-annular cuff portion is positioned proximal to the one or more prosthetic valve elements.
5. The prosthetic heart valve of claim 1 , wherein the stent body is self-expandable.
6. The prosthetic heart valve of claim 1 , wherein the annulus section includes multiple rows of cells.
7. The prosthetic heart valve of claim 1 , wherein the cuff is sutured to cell struts of the stent body.
8. The prosthetic heart valve of claim 1 , wherein the cuff is sutured to junctions between cell struts of the stent body.
9. The prosthetic heart valve of claim 1 , wherein the cuff is formed of animal tissue.
10. The prosthetic heart valve of claim 9 , wherein the cuff is formed of porcine pericardial tissue.
11. The prosthetic heart valve claim 1 , wherein the aortic section has a larger diameter than the proximal end of the stent body when the stent body is in the radially expanded condition.
12. The prosthetic heart valve of claim 1 , wherein the flared region has a larger diameter than the annulus section when the stent body is in the radially expanded condition.
13. The prosthetic heart valve of claim 1 , wherein the inner cuff portion and the outer cuff portion are formed of separate pieces of material.
14. An assembly for delivering a prosthetic heart valve to a target site in a patient, comprising:
(a) a delivery device having a retractable sheath; and
(b) a prosthetic heart valve adapted to be mounted on the delivery device and implanted by the delivery device at the target site as a single unit, the prosthetic heart valve including:
(1) a stent body having a proximal end adjacent an inflow end and a distal end adjacent an outflow end and including an annulus section and a flared region proximal to the annulus section, the stent body having a radially collapsed condition and a radially expanded condition, the annulus section and the flared region increasing in diameter during transition from the radially collapsed condition to the radially expanded condition, the flared region extending from the annulus section to the proximal end of the stent, wherein the stent body further includes an aortic section distal to the annulus section;
(2) one or more prosthetic valve elements mounted to the stent body and operative to allow flow in an antegrade direction from the inflow end to the outflow end but to substantially block flow in a retrograde direction from the outflow end to the inflow end; and
(3) a cuff secured to the stent body, the cuff including an outer cuff portion and an inner cuff portion, the outer cuff portion covering an exterior surface of the flared region, the inner cuff covering an interior surface of the flared region, the outer cuff portion defining a ring having a main portion that projects radially outward farther than any portion of the annulus section of the stent body, and a proximal edge axially offset from the main portion,
wherein the outer cuff portion, in cooperation with the proximal edge of the ring, is adapted for engagement with native tissue proximal to a native valve annulus to form a seal with the native tissue to block retrograde flow around an exterior surface of the stent body.
15. The assembly of claim 14 , wherein the stent body includes a concave curvature extending between the aortic section and the flared region.
16. The assembly of claim 14 , wherein the inner cuff portion includes a supra-annular cuff portion positioned adjacent the annulus section and a sub-annular cuff portion positioned proximal to the supra-annular cuff portion.
17. The assembly of claim 14 , wherein the aortic section has a larger diameter than the proximal end of the stent body when the stent body is in the radially expanded condition.
18. The assembly of claim 14 , wherein the flared region has a larger diameter than the annulus section when the stent body is in the radially expanded configuration.
19. The prosthetic heart valve claim 1 , wherein the main portion projects radially outward farther than any portion of the flared region of the stent body.
20. The prosthetic heart valve claim 1 , wherein the main portion covers an entirety of the flared region.