Stents for autologous tissue heart valve

• US 5,755,782 A
• Filed: 12/17/1993
• Issued: 05/26/1998
• Est. Priority Date: 01/24/1991
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Autogenics Co.
• Inventors: Calvin, John H., Love, Jack W., Love, Charles S.
• Primary Examiner(s): Willse, David H.
• Application Number:
  US08/169,336
• Time in Patent Office: 1,621 Days
• Field of Search: 623/2, 623/900, 24/484, 24/567
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/2409 Support rings therefor, e.g. for connecting valves to tissue annuloplasty rings A61F2/2442
• CPC Class Codes: A61F 2/2412 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 2/2415 Manufacturing methods
• CPC Class Codes: A61F 2/2472 Devices for testing
• CPC Class Codes: Y10S 623/90 Stent for heart valve

Abstract

An improved set of stents for autologous tissue heart valves is provided. The stents are designed with the aid of a computer-aided-design (CAD) system, and nest within each other to securely clamp a piece of tissue which forms the leaflets of the heart valve. The geometrical features of the stents are designed to provide uniform nesting between the stents to prevent the formation of stress raisers on the tissue. Additionally, the windows in the stent posts are narrowed to prevent the suturing needle used during implantation of the valve from becoming lodged in the garter springs which clamp the outer stent to the inner stent. Finally, the sock covering the outer stent is bonded to the stent base at both upper and lower locations to isolate the bonds from the patient'"'"'s blood flow.

Claims

1. An outer stent for securing an inner stent having a base and a plurality of posts extending therefrom and spaced around the base and tissue wrapped thereon, said outer stent spreadable from a relaxed position to a spread position, said outer and inner stents cooperating to form a heart valve implanted into a patient by use of sutures and needles, said outer stent comprising:

a base having a plurality of slots;

a tensioning spring disposed around said base;

a plurality of posts extending upwardly from said base, said posts adapted to register with said inner stent when said inner and outer stents are secured together, at least one of said posts including a window to allow the insertion of the posts of said inner stent therein;

an elastic ring disposed around said base for allowing the securing of said outer stent to said patient; and

a covering emplaced around said base and said posts and bonded to said base at a plurality of locations.

2. The outer stent of claim 1 further comprising a plurality of scalloped portions disposed between said posts.

3. The outer stent of claim 2 wherein each of said scalloped portions contains a cusp at its midsection.

4. The outer stent of claim 1 wherein said posts and said base are shaped so as to prevent said tissue from being pinched when said inner stent has been inserted into said outer stent.

5. An outer stent for securing an inner stent having a base and a plurality of posts extending therefrom and spaced around the base and tissue wrapped thereon, said outer stent spreadable from a relaxed position to a spread position, said outer and inner stents cooperating to form a heart valve implanted into a patient by use of sutures and needles, said outer stent comprising:

a base having a plurality of slots;

a tensioning spring disposed around said base;

a plurality of posts extending upwardly from said base, said posts connected by scalloped portions, said posts adapted to register with said inner stent when said inner and outer stents are secured together, each of said posts including a window to allow the insertion of the posts of said inner stent therein;

an elastic ring disposed around said base for allowing the securing of said outer stent to said patient; and

a covering emplaced around said base and said posts and bonded to said base at a plurality of locations.

6. An outer stent for securing an inner stent having a base and a plurality of posts extending therefrom and spaced around the base and tissue wrapped thereon, said outer stent spreadable from a relaxed position to a spread position, said outer and inner stents cooperating to form a heart valve implanted into a patient by use of sutures and needles, said outer stent comprising:

a frame having an annular lower portion and an upper portion, said lower portion having a plurality of slots, said upper portion integrally formed with and extending upwardly from said lower portion to form a plurality of posts, at least one of said posts having a window to allow the insertion of the posts of said inner stent therein;

a tensioning spring disposed in a circumferential groove formed in an outer surface of said lower portion, said spring causing said lower portion of said frame to clamp said tissue between said inner and outer stents when formed as said heart valve;

an elastic ring disposed around said lower portion for allowing the securing of said outer stent to said patient; and

a covering emplaced around said frame and said ring and bonded to said lower portion of said frame at a plurality of locations.

7. An outer stent for securing an inner stent having a base and a plurality of posts extending therefrom and spaced around the base and tissue wrapped thereon, said outer stent spreadable from a relaxed position to a spread position, said outer and inner stents cooperating to form a heart valve implanted into a patient by use of sutures and needles, said outer stent comprising:

a base having a plurality of slots;

a tensioning spring disposed in a groove formed around said base for providing a radially compressive force about said base and configured to clamp said tissue between said inner and outer stents when formed as said heart valve;

a plurality of posts extending upwardly from said base, said posts adapted to register with said inner stent when said inner and outer stents are secured together, at least one of said posts including a window to allow the insertion of the posts of said inner stent therein;

an elastic ring disposed around said base for allowing the securing of said outer stent to said patient; and

a covering emplaced around said base and said posts and bonded to said base at a plurality of locations.