Minimally-invasive heart valve with cusp positioners

• US 20040186563A1
• Filed: 03/18/2003
• Published: 09/23/2004
• Est. Priority Date: 03/18/2003
• Status: Active Grant

• Current Assignee: Edwards Lifesciences Corporation
• Original Assignee: Edwards Lifesciences Corporation
• Inventors: Lobbi, Mario M.
• Granted Patent: US 7,399,315 B2
• Time in Patent Office: Days
• US Class Current: 623/2.11
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61F 2/2412 with soft flexible valve members, e.g. tissue valves shaped like natural valves check valves with flexible valve members in general F16K15/14
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2/2427 Devices for manipulating or deploying heart valves during implantation
• CPC Class Codes: A61F 2/243 Deployment by mechanical expansion
• CPC Class Codes: A61F 2/2436 Deployment by retracting a sheath
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/9525 using a funnel
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/0066 stapled
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable

Abstract

A prosthetic heart valve having an internal support frame with a continuous, undulating leaflet frame defined therein. The leaflet frame has three cusp regions positioned at an inflow end intermediate three commissure regions positioned at an outflow end thereof. The leaflet frame may be cloth covered and flexible leaflets attached thereto form occluding surfaces of the valve. The support frame further includes three cusp positioners rigidly fixed with respect to the leaflet frame and located at the outflow end of the support frame intermediate each pair of adjacent commissure regions. The valve is desirably compressible so as to be delivered in a minimally invasive manner through a catheter to the site of implantation. Upon expulsion from catheter, the valve expands into contact with the surrounding native valve annulus and is anchored in place without the use of sutures. In the aortic valve position, the cusp positioners angle outward into contact with the sinus cavities, and compress the native leaflets if they are not excised, or the aortic wall if they are. The support frame may be formed from a flat sheet of Nitinol that is bent into a three-dimensional configuration and heat set. A holder having spring-like arms connected to inflow projections of the valve may be used to deliver, reposition and re-collapse the valve, if necessary.

Claims

1. A prosthetic heart valve support frame, comprising:

a continuous, undulating valve leaflet frame that mimics the natural fibrous structure of an aortic valve, the leaflet frame having three cusp regions alternating with and intermediate three commissure regions, the three cusp regions being positioned at an inflow end of the support frame and circumferentially about a flow axis defined within the support frame, the three commissure regions being positioned at an outflow end of the support frame and circumferentially about the flow axis; and

three cusp positioners rigidly fixed with respect to the leaflet frame and disposed circumferentially about the flow axis, each cusp positioner being located at the outflow end of the support frame and intermediate two of the commissure regions of the leaflet frame.

2. The heart valve support frame of claim 1, wherein the leaflet frame and the cusp positioners are formed integrally as a single piece.

3. The heart valve support frame of claim 2, wherein the support frame is formed by a process comprising:

providing a two-dimensional blank of the support frame; and

forming the two-dimensional blank into the three-dimensional heart valve support frame.

4. The heart valve support frame of claim 1, wherein the leaflet frame and the cusp positioners are made of Nitinol.

5. The heart valve support frame of claim 1, wherein the Nitinol has a martensitic transition temperature of less than about 5°

C. and an austenitic transition temperature of more than about 20°

C.

6. The heart valve support frame of claim 1, wherein each cusp positioner has a U-shape with an apex of the U-shape pointing toward the outflow end of the support frame and two legs of the U-shape pointing toward the inflow end.

7. The heart valve support frame of claim 6, wherein each of the two legs of each U-shaped cusp positioner is rigidly fixed to the continuous leaflet frame at a location approximately midway between a cusp region and a commissure region thereof.

8. The heart valve support frame of claim 6, further including an anti-migration member rigidly fixed to each cusp positioner and projecting therefrom.

9. The heart valve support frame of claim 8, wherein each anti-migration member comprises an elongated section terminating in an enlarged and rounded head.

10. The heart valve support frame of claim 1, wherein the support frame further includes three cusp connectors rigidly fixed with respect to the leaflet frame and disposed circumferentially about the flow axis, each cusp connector being located at the inflow end of the support frame and intermediate two of the cusp regions of the leaflet frame.

11. The heart valve support frame of claim 10, wherein each cusp connector has a U-shape with an apex of the U-shape pointing toward the inflow end of the support frame and two legs of the U-shape pointing toward the outflow end.

12. The heart valve support frame of claim 10, wherein the leaflet frame, cusp positioners, and cusp connectors are formed integrally as a single piece, and wherein the three cusp positioners and three cusp connectors define a continuous, undulating shape that generally mimics the shape of the leaflet frame but is rotated 60°

about the flow axis therefrom.

13. The heart valve support frame of claim 1, wherein the cusp positioners flare outwardly from the rest of the support frame.

14. A collapsible prosthetic heart valve, comprising:

a collapsible leaflet frame having three cusp regions intermediate three commissure regions, the three cusp regions being positioned at an inflow end of the leaflet frame and circumferentially about a flow axis defined within the support frame, the three commissure regions being positioned at an outflow end of the leaflet frame and circumferentially about the flow axis;

three separate, flexible leaflets attached to the leaflet frame, each leaflet having an arcuate cusp edge opposite a free edge and a pair of commissure edges therebetween, the leaflets being attached around the leaflet frame with the cusp edge of each leaflet extending along one of the cusp regions, and a commissure edge of each leaflet meeting a commissure edge of an adjacent leaflet at one of the commissure regions; and

three cusp positioners rigidly fixed with respect to the leaflet frame and disposed circumferentially about the flow axis, each cusp positioner being located at the outflow end of the leaflet frame and intermediate two of the commissure regions of the leaflet frame.

15. The heart valve of claim 14, wherein each cusp positioner has a U-shape with an apex of the U-shape pointing toward the outflow end of the leaflet frame and two legs of the U-shape pointing toward the inflow end.

16. The heart valve of claim 15, wherein each of the two legs of each U-shaped cusp positioner is rigidly fixed to the continuous leaflet frame at a location approximately midway between a cusp region and a commissure region thereof.

17. The heart valve of claim 15, further including an anti-migration member rigidly fixed to each cusp positioner and projecting therefrom.

18. The heart valve of claim 14, wherein the heart valve further includes three cusp connectors rigidly fixed with respect to the leaflet frame and disposed circumferentially about the flow axis, each cusp connector being located at the inflow end of the leaflet frame and intermediate two of the cusp regions of the leaflet frame.

19. The heart valve of claim 18, wherein each cusp connector has a U-shape with an apex of the U-shape pointing toward the inflow end of the leaflet frame and two legs of the U-shape pointing toward the outflow end.

20. The heart valve of claim 19, wherein the leaflet frame, cusp positioners, and cusp connectors are formed integrally as a single piece, and wherein the three cusp positioners and three cusp connectors define a continuous, undulating shape that generally mimics the shape of the leaflet frame but is rotated 60°

about the flow axis therefrom.

21. The heart valve of claim 18, wherein an inflow periphery of the heart valve is defined along the alternating and rigidly fixed cusp regions and cusp connectors.

22. The heart valve of claim 21, wherein the inflow periphery has an external fabric covering, and wherein the heart valve further includes a fabric panel defining an exterior surface of the heart valve between each pair of cusp positioner and cusp connector.

23. The heart valve of claim 14, wherein the leaflet frame has a fabric covering along substantially its entire length, the fabric covering defining a flange, wherein the arcuate cusp edges of the flexible leaflets attach to the fabric covering flange.

24. The heart valve of claim 23, wherein the fabric covering flange projects generally outward from the leaflet frame and the cusp edges of the flexible leaflets extend radially outward past and underneath the leaflet frame and are sewn to the fabric covering flange.

25. The heart valve of claim 14, wherein each flexible leaflet has a pair of tabs extending on either side of its free edge, wherein two tabs of adjacent flexible leaflets meet and pass together to the outside of the adjacent commissure region of the leaflet frame and are attached thereto using sutures through the tabs.

26. A collapsible prosthetic heart valve, comprising:

a continuous, collapsible leaflet frame having three U-shaped cusp regions intermediate three U-shaped commissure regions, the three cusp regions being positioned at an inflow end of the leaflet frame and circumferentially about a flow axis defined within the leaflet frame, the three commissure regions being positioned at an outflow end of the leaflet frame and circumferentially about the flow axis;

a cloth covering extending around the leaflet frame; and

three separate, flexible leaflets attached to the leaflet frame, each leaflet having an arcuate cusp edge opposite a free edge and a pair of commissure edges therebetween, the leaflets being attached around the leaflet frame with the cusp edge of each leaflet extending along one of the cusp regions, and a commissure edge of each leaflet meeting a commissure edge of an adjacent leaflet at one of the commissure regions, the commissure edges of each leaflet further including a tab, wherein the tabs of two adjacent leaflets extend through the U-shape commissure region, diverge on the outside of commissure region, and are attached to the leaflet frame on the outside of the commissure region.

27. The prosthetic heart valve of claim 26, further comprising three cusp positioners rigidly fixed with respect to the leaflet frame and disposed circumferentially about the flow axis, each cusp positioner being located at the outflow end of the support frame and intermediate two of the commissure regions of the leaflet frame, each cusp positioner having a U-shape with an apex of the U-shape pointing toward the outflow end of the leaflet frame and two legs of the U-shape pointing toward the inflow end.

28. The heart valve of claim 26, wherein the heart valve further includes three cusp connectors rigidly fixed with respect to the leaflet frame and disposed circumferentially about the flow axis, each cusp connector being located at the inflow end of the leaflet frame and intermediate two of the cusp regions of the leaflet frame.

29. The heart valve of claim 28, wherein an inflow periphery of the heart valve is defined along the alternating and rigidly fixed cusp regions and cusp connectors.

30. The heart valve of claim 26, wherein the leaflet frame has a fabric covering along substantially its entire length, the fabric covering defining a flange, wherein the arcuate cusp edges of the flexible leaflets attach to the fabric covering flange.

31. The heart valve of claim 30, wherein the fabric covering flange projects generally outward from the leaflet frame and the cusp edges of the flexible leaflets extend radially outward past and underneath the leaflet frame and are sewn to the fabric covering flange.

32. A method of implanting a prosthetic aortic heart valve, comprising:

providing a collapsible prosthetic heart valve having a collapsible leaflet frame defined by three cusp regions on an inflow end of the valve intermediate three commissure regions on an outflow end of the valve, the valve further including three cusp positioners on the outflow end and intermediate the three commissure regions;

collapsing the prosthetic heart valve within a delivery tube;

advancing the prosthetic heart valve within the delivery tube to an aortic annulus;

expelling the prosthetic heart valve from the delivery tube by relative movement therebetween;

expanding the prosthetic heart valve; and

positioning the prosthetic heart valve such that the cusp positioners contact the two coronary and one non-coronary sinuses of the ascending aorta without blocking the coronary ostia.

33. The method of claim 32, further including:

connecting a holder having flexible members to the commissure regions of the prosthetic heart valve and utilizing the flexible members to perform the step of positioning the prosthetic heart valve.

34. The method of claim 33, further including:

connecting flexible members of the holder to the cusp positioners and utilizing the flexible members to perform the step of positioning the prosthetic heart valve.

35. The method of claim 33, further including utilizing the flexible members to rotate the prosthetic heart valve during the step of positioning.

36. The method of claim 33, further including utilizing the flexible members to re-collapse the prosthetic heart valve after the step of expanding.

37. The method of claim 32, wherein the prosthetic heart valve is expanded in a location that is inferior to a final implant position such that the cusp positioners contact the surrounding aortic annulus, and the step of positioning comprises displacing the valve in a superior direction to a final implant position.

38. The method of claim 37, wherein the cusp positioners are flared outward to define a circle about a flow axis of the valve greater than a circle about the flow axis defined by the three commissure regions, and wherein the step of displacing the valve in a superior direction causes the outwardly flared cusp positioners to be channeled into perspective coronary sinuses.

39. The method of claim 32, wherein the collapsible leaflet frame is formed of a shape memory alloy having an austenitic transition temperature less than body temperature, and wherein the step of collapsing is done with the material of the leaflet frame at a temperature at or below its martensitic transition temperature.

40. The method of claim 39, wherein the step of collapsing is done in conjunction with immersing the prosthetic heart valve in an ice bath to reduce the temperature of the material of leaflet frame to less than or equal to its martensitic transition temperature.

41. The method of claim 32, wherein the collapsible leaflet frame is formed of a shape memory alloy having a memory condition in its expanded state, and wherein the step of expanding the prosthetic heart valve comprises both permitting self-expansion of the valve to an intermediate diameter and then using a physical expander to increase the diameter of the valve to the memory condition of the leaflet frame.

42. A method of implanting a collapsible prosthetic heart valve, comprising:

providing a self-expanding valve comprised of a material displaying hysteresis in the elastic or superelastic region;

permitting the valve to self-expand to a first diameter; and

assisting the valve with a physical expander to further expand to a second diameter.

43. The method of claim 42, wherein the prosthetic heart valve includes a collapsible leaflet frame formed of a shape memory alloy having an austenitic transition temperature less than body temperature, and further including a step of collapsing the valve with the material of the leaflet frame at a temperature at or below its martensitic transition temperature.

44. The method of claim 43, wherein the step of collapsing is done in conjunction with immersing the prosthetic heart valve in an ice bath to reduce the temperature of the material of leaflet frame to less than or equal to its martensitic transition temperature.

45. The method of claim 42, wherein the physical expander is a balloon.

46. The method of claim 42, wherein the prosthetic heart valve has a collapsible leaflet frame defined by three cusp regions on an inflow end of the valve intermediate three commissure regions on an outflow end of the valve, the valve further including three cusp positioners on the outflow end and intermediate the three commissure regions, the method further including:

collapsing the prosthetic heart valve within a delivery tube;

advancing the prosthetic heart valve within the delivery tube to an aortic annulus;

expelling the prosthetic heart valve from the delivery tube by relative movement therebetween;

expanding the prosthetic heart valve by the steps of permitting self-expansion and assisting further expansion; and

positioning the prosthetic heart valve such that the cusp positioners contact the two coronary and one non-coronary sinuses of the ascending aorta without blocking the coronary ostia.

47. The method of claim 46, further including:

connecting a holder having flexible members to the commissure regions of the prosthetic heart valve and utilizing the flexible members to perform the step of positioning the prosthetic heart valve.

48. The method of claim 47, further including:

connecting flexible members of the holder to the cusp positioners and utilizing the flexible members to perform the step of positioning the prosthetic heart valve.

49. The method of claim 47, further including utilizing the flexible members to rotate the prosthetic heart valve during the step of positioning.

50. The method of claim 47, further including utilizing the flexible members to re-collapse the prosthetic heart valve after the step of expanding.