Valve assembly for crimp profile
A method of assembling a prosthetic heart valve includes providing a collapsible and expandable stent having an annulus section and an aortic section. The annulus section has a first diameter in a relaxed condition and a second diameter less than the first diameter in a collapsed condition. A constraint is applied to the stent to constrain the annulus section to a predetermined diameter between the first and second diameters. Applying a cuff and/or a plurality of leaflets to the stent in the constrained condition enables less material to be used. The resultant prosthetic valve is therefore able to be collapsed to a smaller diameter for introduction into a patient.
1. A method of assembling a prosthetic heart valve, comprising:
providing a collapsible and expandable stent having an annulus section and an aortic section, the annulus section having a first annulus diameter in a relaxed condition and a second annulus diameter less than the first annulus diameter in a collapsed condition;
applying a constraint to the stent to constrain the annulus section to a predetermined annulus diameter between the first annulus diameter and the second annulus diameter;
after applying the constraint, assembling at least one of a cuff or a plurality of leaflets to the constrained annulus section to form a prosthetic heart valve; and
removing the constraint from the stent prior to implantation of the prosthetic heart valve within a native valve annulus.
2. The method of claim 1 , wherein the aortic section has a first aortic diameter in the relaxed condition and a second aortic diameter less than the first aortic diameter in the collapsed condition, and the step of applying the constraint constrains the aortic section to a predetermined aortic diameter between the first aortic diameter and the second aortic diameter.
3. The method of claim 2 , wherein the constraint comprises a first suture tied to the annulus section of the stent to constrain the diameter of the annulus section to the predetermined annulus diameter and a second suture tied to the aortic section of the stent to constrain the diameter of the aortic section to the predetermined aortic diameter.
4. The method of claim 1 , wherein the predetermined annulus diameter is between about 85% and about 95% of the first annulus diameter.
5. The method of claim 1 , wherein the constraint comprises at least one drawstring to constrain the diameter of the annulus section.
6. The method of claim 5 , wherein the at least one drawstring comprises a first suture tied to the annulus section of the stent to constrain the diameter of the annulus section to the predetermined annulus diameter.
7. The method of claim 6 , wherein the removing step includes cutting the first suture to release the annulus section to an unconstrained annulus diameter between the predetermined annulus diameter and the first annulus diameter.
8. The method of claim 1 , wherein the constraint comprises at least one ring disposed about a circumference of the stent to constrain the diameter of the stent.
9. The method of claim 1 , wherein the constraint comprises a first ring disposed about the annulus section of the stent and a second ring disposed about the aortic section of the stent.
10. The method of claim 9 , wherein the first ring and the second ring are coupled together by a helical portion.
11. The method of claim 10 , further comprising rotating the constraint with respect to the stent to facilitate the assembling step.
12. The method of claim 1 , wherein the constraint comprises a cylindrical body having a proximal opening, a distal opening, a lumen defined between the proximal opening and the distal opening, and at least one window in the body configured and arranged to permit assembly of the prosthetic heart valve therethrough.
13. The method of claim 12 , wherein the at least one window comprises three triangular windows evenly spaced about the circumference of the constraint.
14. The method of claim 12 , wherein the constraint further comprises a cone portion at the distal opening.
15. The method of claim 12 , further comprising cutouts in the body spaced to facilitate assembly of the heart valve.
16. The method of claim 1 , wherein the constraint further comprises at least two rings and a plurality of angled struts coupled to the at least two rings, the plurality of angled struts outlining a plurality of triangles.