Hybrid heart valves adapted for post-implant expansion

• US 10,695,170 B2
• Filed: 06/30/2016
• Issued: 06/30/2020
• Est. Priority Date: 07/02/2015
• Status: Active Grant

• Current Assignee: Edwards Lifesciences Corporation
• Original Assignee: Edwards Lifesciences Corporation
• Inventors: Conklin, Brian S., Zeng, Qinggang
• Primary Examiner(s): Mathew, Seema
• Application Number:
  US15/199,743
• Publication Number:
  US 20170000603A1
• Time in Patent Office: 1,461 Days
• CPC Class Codes: A61F 2/2409 Support rings therefor, e.g. for connecting valves to tissue annuloplasty rings A61F2/2442
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2433 using balloon catheter
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2210/0057 stretchable
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0052 T-shaped
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2230/0067 conical
• CPC Class Codes: A61F 2250/001 for adjusting a diameter
• CPC Class Codes: A61F 2250/0012 for adjusting elasticity, flexibility, spring rate or mechanical tension
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0021 differing in coefficient of friction
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: A61F 2250/0048 differing in mechanical expandability, e.g. in mechanical, self- or balloon expandability
• CPC Class Codes: A61F 2250/0089 coded with symbols, e.g. dots, numbers, letters, words

Abstract

A hybrid prosthetic heart valve configured to replace a native heart valve and having a support frame configured to be expanded post implant in order to receive and/or support an expandable prosthetic heart valve therein (a valve-in-valve procedure). The prosthetic heart valve may be configured to have a generally rigid and/or expansion-resistant configuration when initially implanted to replace a native valve (or other prosthetic heart valve), but to assume a generally expanded form when subjected to an outward force such as that provided by a dilation balloon or other mechanical expander. An inflow stent frame is expandable for anchoring the valve in place, and may have an outflow end that is collapsible for delivery and expandable post-implant to facilitate a valve-in-valve procedure.

Claims

1. A hybrid prosthetic heart valve configured for surgical delivery and adapted for post-implant expansion and having an inflow end and an outflow end, comprising:

a valve member including a plurality of flexible leaflets configured to ensure one-way blood flow therethrough and a leaflet support structure defining alternating cusps and commissures to which peripheral edges of the leaflets attach, the leaflet support structure being configured with a relatively stable diameter, the leaflet support structure also being absent of any rigid circular elements configured to inhibit radial expansion; and

a plastically-expandable inflow stent frame secured to and projecting from an inflow end of the leaflet support structure and having a strength requiring a predetermined expansion force to convert to an expanded state, the stent frame comprising a plurality of expandable struts and an upper edge at an outflow end of the stent frame that undulates with peaks and valleys to at least partially conform to the undulating leaflet support structure, and further wherein the upper edge defines an implant circumference with a functional diameter that enables physiological functioning of the valve member when implanted, wherein the upper edge cannot be radially compressed by more than 2-3 mm such that the hybrid prosthetic heart valve is unsuitable for delivery to a heart valve annulus via compression and transcatheter delivery, wherein the outflow edge of the stent frame includes three integrated commissure posts located adjacent to and radially outward from the leaflet support structure commissures to which the leaflets attach outside of the leaflet support structure, and wherein the upper edge is configured to expand a limited amount from the functional diameter to an enlarged diameter larger than the functional diameter upon application of an outward dilatory force from within the outflow end substantially larger than forces associated with normal physiological use.

2. The prosthetic heart valve of claim 1, wherein the stent frame includes a plurality of circumferential row struts connected by a series of spaced axial column struts, and the upper edge comprises an outflow row strut that extends continuously around a periphery of the stent frame and has a series of spaced V-shaped notches that permit limited expansion and contraction.

3. The prosthetic heart valve of claim 2, wherein the outflow row strut has limited radially compressibility of between about 7-20% of the functional diameter to reduce the size of the outflow end during delivery of the heart valve.

4. The prosthetic heart valve of claim 1, wherein the leaflet support structure comprises an undulating wireform with alternating cusps and commissures.

5. The prosthetic heart valve of claim 4, wherein the flexible leaflets have peripheral edges, and the wireform is the only structural support to which the flexible leaflets attach along their entire peripheral edges.

6. The prosthetic heart valve of claim 1, wherein the integrated commissure posts are separate elements secured with sutures directly to the stent frame outflow edge and otherwise not connected to each other circumferentially.

7. The prosthetic heart valve of claim 1, wherein the integrated commissure posts are integrally formed of the same homogeneous material as the rest of the stent frame.

8. The prosthetic heart valve of claim 1, wherein the upper edge of the stent frame is configured to expand below each of the leaflet support structure commissures upon application of the outward dilatory force.

9. The prosthetic heart valve of claim 1, further including an identifier on the stent frame visible from outside the body after implant that identifies the stent frame as having an expandable outflow end.

10. A hybrid prosthetic heart valve configured for surgical delivery and adapted for post-implant expansion and having an inflow end and an outflow end, comprising:

a valve member including an undulating wireform with alternating cusps and commissures supporting a plurality of flexible leaflets configured to ensure one-way blood flow therethrough, the wireform being configured with a relatively stable diameter, the valve member also being absent of any rigid circular elements configured to inhibit radial expansion; and

a plastically-expandable inflow stent frame having a radially-expandable inflow end and an outflow end secured to and projecting from an inflow end of the wireform, wherein the outflow end of the stent frame undulates with peaks and valleys corresponding to the wireform, and further wherein the outflow end includes three commissure posts located adjacent to and radially outward from the wireform commissures to which the leaflets attach outside of the wireform, the three commissure posts being secured directly to an upper circumferential row of struts defining a functional diameter that enables physiological functioning of the valve member when implanted, the upper circumferential row of struts being radially compressible to a smaller contracted diameter to enable compression of the outflow end during delivery of the heart valve, wherein the upper circumferential row of struts cannot be radially compressed by more than 2-3 mm such that the hybrid prosthetic heart valve is unsuitable for delivery to a heart valve annulus via compression and transcatheter delivery, and the upper circumferential row of struts also being radially expandable a limited amount from the functional diameter to a larger expanded diameter upon application of an outward dilatory force from within the stent frame substantially larger than forces associated with normal physiological use.

11. The prosthetic heart valve of claim 10, wherein the upper circumferential row of struts of the stent frame is configured to expand below each of the commissure posts upon application of the outward dilatory force.

12. The prosthetic heart valve of claim 10, further including an identifier on the stent frame visible from outside the body after implant that identifies the stent frame as having an expandable outflow end.

13. The prosthetic heart valve of claim 10, wherein the stent frame has a series of axial slits below each of the commissure posts that permit expansion of the outflow end upon application of the outward dilatory force.

14. The prosthetic heart valve of claim 10, wherein the stent frame has a series of compression sections including spaces that enable a limited compression of the circumferential structure.

15. The prosthetic heart valve of claim 10, wherein the upper circumferential row of struts extends continuously around a periphery of the stent frame having the peaks and valleys corresponding to the wireform, and the upper circumferential row of struts has a series of spaced V-shaped notches that permit limited expansion and contraction.

16. The prosthetic heart valve of claim 15, wherein the upper circumferential row of struts has limited radially compressibility of between about 7-20% of the functional diameter to reduce the size of the outflow end during delivery of the heart valve.

17. The prosthetic heart valve of claim 10, wherein the commissure posts are separate elements secured with sutures directly to the upper circumferential row of struts and otherwise not connected to each other circumferentially.

18. The prosthetic heart valve of claim 10, wherein the commissure posts extend upward from a circumferential band secured with sutures directly to the upper circumferential row of struts, the band being configured to break upon application of an outward dilatory force from within the stent frame sufficient to cause the upper circumferential row of struts to expand from the functional diameter to the expanded diameter.

19. The prosthetic heart valve of claim 18, wherein the circumferential band is positioned immediately above the stent frame.

20. The prosthetic heart valve of claim 18, wherein the circumferential band is located partly radially within the stent frame in an overlapping manner.

21. The prosthetic heart valve of claim 10, wherein the flexible leaflets have peripheral edges, and the wireform is the only structural support to which the flexible leaflets attach along their entire peripheral edges.