Transcatheter valve having reduced seam exposure
A transcatheter valve having an expandable frame and a collapsible multi-portion skirt within the frame are provided with seams between the portions of the skirt that are located to cooperate with features of the frame and thereby reduce the exposure of the seams.
1. A valve prosthesis comprising:
a. a self-expanding frame comprising struts and nodes which define a plurality of cells, the frame being generally cylindrical with a longitudinal axis and an inflow end;
b. a valve body supported by the frame and comprising:
i. a plurality of leaflets sewn to a skirt to form joints between each leaflet and the skirt, in which each joint between each leaflet and the skirt is curved to define upper and lower portions of each joint as a whole, in which adjacent joints come together in the upper portion, and an apex of a curve lies in the lower portion,
ii. adjoining leaflets sewn together to form commissures which are sewn to the frame downstream of the inflow end, and
iii. a bottom edge sewn to the inflow end of the frame, and
iv. at least one side seam, each of which side seams extends only between a lower portion of a joint and the bottom edge.
2. The valve prosthesis of claim 1 , in which the lower portion of the joint has a lower apex region, and the side seam extends between the lower apex region and the bottom edge.
3. The valve prosthesis of claim 1 , in which at least one side seam is substantially parallel to the longitudinal axis.
4. The valve prosthesis of claim 1 , in which at least one side seam makes an acute angle with the longitudinal axis.
5. The valve prosthesis of claim 1 , in which the skirt comprises three substantially identical portions, and each portion is asymmetric about an axis substantially aligned with the longitudinal direction.
6. The valve prosthesis of claim 1 , in which the skirt has three substantially identical portions, a bottom edge of each portion comprises five end tabs symmetrically arranged about an axis of the skirt which is substantially aligned with the longitudinal axis and passes through an upper apex of such portion, and at least one side seam extends between the lower apex region and an end tab which does not lie on the axis of the skirt.
7. The valve prosthesis of claim 1 , in which the skirt is aligned with the frame such that at least one side seam substantially follows a line defined by three immediately adjacent nodes.
8. The valve prosthesis of claim 1 , in which the skirt is aligned with the frame such that at least one side seam and a line defined by three immediately adjacent nodes are aligned with each other within ±1 mm.
9. A valve prosthesis comprising a self-expanding frame having a longitudinal axis and an inflow end, and comprising a plurality of cells; and a valve body having a skirt with a bottom edge sewn to the inflow end of the frame, a plurality of leaflets sewn to the skirt along a joint having upper and lower portions, in which adjacent leaflets come together in the upper portion, and an apex of a curve of the joint as a whole lies in the lower portion, and at least one side seam, each of which side seams extends only between the lower portion and the bottom edge.
10. The valve prosthesis of claim 9 , in which the lower portion of the joint has a lower apex region, and the side seam extends between the lower apex region and the bottom edge.
11. The valve prosthesis of claim 9 , in which at least one side seam is substantially parallel to the longitudinal axis.
12. The valve prosthesis of claim 9 , in which at least one side seam makes an acute angle with the longitudinal axis.
13. The valve prosthesis of claim 9 , in which the skirt comprises three substantially identical portions, and each portion is asymmetric about an axis substantially aligned with the longitudinal direction.
14. The valve prosthesis of claim 9 , in which the skirt has three substantially identical portions, a bottom edge of each portion comprises five end tabs symmetrically arranged about an axis of the skirt which is substantially aligned with the longitudinal axis and passes through an upper apex of such portion, and at least one side seam extends between the lower apex region and an end tab which does not lie on the axis of the skirt.
15. The valve prosthesis of claim 9 , in which the frame comprises struts and nodes, and the skirt is aligned with the frame such that at least one side seam substantially follows a line defined by three immediately adjacent nodes.
16. The valve prosthesis of claim 9 , in which the frame comprises struts and nodes, and the skirt is aligned with the frame such that at least one side seam and a line defined by three immediately adjacent nodes are aligned with each other within ±1 mm.