Multi-frame prosthetic valve apparatus and methods
Described embodiments are directed toward centrally-opening leaflet prosthetic valve devices having a leaflet frame coaxially disposed within a body frame, as well as methods of making the valve devices.
1. A valve comprising:
a body frame formed into a cylindrical structure having a body frame inner surface defining a body frame lumen;
a leaflet frame that is coaxial with and nested within the body frame and includes a plurality of posts, wherein at least a portion of the leaflet frame is not held in engagement with the body frame inner surface such that the plurality of posts are operable to flex under loading during valve operation, the leaflet frame further including a plurality of U-shaped portions, each adjacent pair of the plurality of U-shaped portions being connected at one of the plurality of posts; and
a plurality of leaflets supported by the plurality of posts of the leaflet frame, each of the plurality of leaflets having a U-shaped base that follows a U-shaped portion of one of the plurality of U-shaped portions of the leaflet frame.
2. The valve of claim 1 , wherein;
the plurality of posts are disposed entirely between axial inflow and outflow ends of the body frame; and
the portion of the leaflet frame not held in engagement with the body frame includes at least a portion of the plurality of posts.
3. The valve of claim 1 , wherein the plurality of posts at least partially extend beyond an axial outflow end of the body frame.
4. The valve of claim 1 , further comprising a film positioned between the leaflet frame and the body frame, wherein the at least a portion of the leaflet frame is not coupled to the film positioned between the leaflet frame and the body frame.
5. The valve of claim 1 , wherein the body frame and the leaflet frame have different stiffnesses.
6. The valve of claim 1 , wherein:
an outflow end of the body frame forms a plurality of valleys around a circumference of the body frame; and
each of the plurality of posts of the leaflet frame is aligned with an apex of a respective one of the plurality of valleys of the body frame.
7. A valve comprising:
a body frame formed into a cylindrical structure including a body frame inner surface defining a body frame lumen;
a leaflet frame that is coaxial with and nested within the body frame such that the leaflet frame is positioned within the body frame lumen, the leaflet frame including a plurality of posts partially engaging the body frame, wherein:
each of the plurality of posts includes an end that is free from the body frame; and
a majority of each of the plurality of posts is disposed between axial inflow and outflow ends of the body frame; and
a plurality of leaflets supported by the plurality of posts of the leaflet frame.
8. The valve of claim 7 , wherein engagement of the plurality of posts of the leaflet frame with the body frame provides support to the leaflet frame and allows for transfer of loading on the plurality of leaflets to the leaflet frame and to the body frame.
9. The valve of claim 7 , wherein the body frame and the leaflet frame have different stiffnesses.
10. The valve of claim 7 , wherein each of the plurality of leaflets is coupled to the leaflet frame such that each leaflet has a U-shaped base.
11. A valve comprising:
a multi-part frame defining a flow lumen through which fluid is able to selectively flow, the multi-part frame including:
an outer frame having an annular form, the outer frame defining an outer frame lumen;
a leaflet frame defining a plurality of commissure posts, each of the plurality of commissure posts include a free end, the leaflet frame being at least partially received within the outer frame lumen and fixedly coupled to the outer frame, wherein:
the free end of each of the plurality of commissure posts is not held in engagement with the outer frame during valve operation and is operable to flex under loading during valve operation;
the leaflet frame comprises a plurality of U-shaped portions; and
each adjacent pair of the plurality of U-shaped portions is connected at one of the plurality of commissure posts; and
a plurality of leaflets coupled to the leaflet frame, each leaflet having a U-shaped base that follows a U-shaped portion of one of the plurality of U-shaped portions of the leaflet frame, the plurality of leaflets being moveable between an open position and a closed position to selectively block and unblock the flow lumen.
12. The valve of claim 11 , further comprising a cover material positioned between the leaflet frame and the outer frame.
13. The valve of claim 11 , wherein the leaflet frame and the outer frame are configured to flex relative to one another during valve operation.
14. The valve of claim 11 , wherein the outer frame and the leaflet frame have different stiffnesses.
15. The valve of claim 11 , wherein the plurality of commissure posts are configured to flex inwardly and outwardly with respect to the outer frame during valve operation.
16. The valve of claim 11 , wherein the multi-part frame is configured to permit flexing between the leaflet frame and the outer frame.
17. The valve of claim 11 , wherein at least a majority of an axial dimension of the plurality of commissure posts is disposed between inflow and outflow ends of the outer frame.
18. The valve of claim 11 , wherein:
an outflow end of the outer frame forms a plurality of valleys around a circumference of the outer frame; and
each of the plurality of commissure posts of the leaflet frame is aligned with an apex of a respective one of the plurality of valleys of the outer frame.
19. The valve of claim 7 , wherein each of the plurality of posts of the leaflet frame is disposed entirely between the axial inflow and outflow ends of the body frame.
20. The valve of claim 7 , wherein each of the plurality of posts of the leaflet frame extends beyond the axial outflow end of the body frame.