MINIMALLY INVASIVE HEART VALVE REPLACEMENT

• US 20090005863A1
• Filed: 08/15/2008
• Published: 01/01/2009
• Est. Priority Date: 02/16/2006
• Status: Active Grant

• Current Assignee: Venus Medtech (Hangzhou), Inc.
• Original Assignee: Transcatheter Technologies Gmbh
• Inventors: GOETZ, Wolfgang, LIM, Hou-Sen
• Granted Patent: US 7,837,727 B2
• Time in Patent Office: Days
• US Class Current: 623/2.180
• 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 2/2439 Expansion controlled by filaments
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2250/0059 temporary
• CPC Class Codes: A61F 2250/006 modular

Abstract

A replacement valve for implantation centrally within the orifice of a malfunctioning native heart valve. The valve is designed for minimally invasive entry through an intercostal opening in the chest of a patient and an opening in the apex of the human heart. The replacement valve includes either a separate anchor (11, 87, 111) or a combined anchor (67) that folds around the malfunctioning native valve leaflets, sandwiching them in a manner so as to securely anchor the replacement valve in a precise, desired location.

Claims

1. A minimally invasive implantable replacement heart valve, which valve comprises:

an outermost envelope portion of shape-memory material having distal and proximal arms for sandwiching the native leaflets of a stenotic valve between said arms, said distal arms being designed to evert and wrap around the native leaflets,

said arms being spaced apart from one another and formed so as to permit them to be individually controlled in their sandwiching of the native leaflets,

a collapsible-expandable heart valve stent of generally tubular shape which includes proximal and distal rings and at least three spaced apart posts that extend axially between said rings, and

a valvular device comprising a plurality of flexible leaflets disposed interior of said stent, which leaflets open to permit blood flow in a downstream direction and close to prevent blood flow in an upstream direction therethrough.

2. The replacement heart valve according to claim 1 wherein said proximal and distal rings are made of undulating wire-like form of a material having a flexibility that allows their collapsing and expanding to change the diameter of the rings.

3. The replacement heart valve according to claim 2 wherein said rings have a memory that causes them to expand to a larger diameter at the temperature within the human body when radially unrestrained and wherein said stent includes eyelet means through which strings may be routed to control such expansion.

4. The replacement heart valve according to claim 1 wherein said at least three spaced-apart longitudinal posts are equiangularly spaced apart and are integral at their ends with said proximal and distal rings.

5. The replacement heart valve according to claim 4 wherein each of said posts has said eyelet means located near its distal and proximal ends through which strings can be passed to exert radially inward force to control expansion of said stent and to reduce its diameter if desired.

6. The replacement heart valve according to claim 1 wherein said outermost envelope portion comprises at least four of said distally extending arms and at least four of said proximally extending arms of shape-memory material, which at least eight arms have eyelets at the ends thereof to facilitate individual control, and wherein said individually controllable distally extending arms are constructed to wrap around the native leaflets by bending back toward said proximally extending arms and contacting downstream-facing surfaces of the native leaflets.

7. The replacement heart valve according to claim 6 wherein said individually controllable proximally extending arms are constructed to swing radially outward at their free ends toward said bent-back distal arms and contact upstream-facing surfaces of the native leaflets.

8. The replacement heart valve according to claim 7 wherein said plurality of individually controllable arms are integral with said stent.

9. The replacement heart valve according to claim 6 wherein said outermost envelope portion is formed separately from said heart valve stent and wherein said stent is designed with a complementary shape to mate with a radially interior shaped region of said envelope portion by interengaging therewith after said envelope portion has been implanted in a native valve.

10. The replacement heart valve according to claim 9 wherein said outermost envelope portion has a circular framework which is formed with a C-shaped axial cross section wherein string can be routed to control expansion of said framework or effect reduction of the diameter thereof.

11. An anchoring device for securing a percutaneously implantable replacement heart valve in an existing valve in the human heart, which device comprises:

a framework of generally tubular shape which is constructed of shape-memory material and includes a central portion, a distal portion and a proximal portion that are integral with one another, said distal portion comprising a plurality of individually controllable arms which evert as a result of temperature change and wrap around the free ends of native leaflets of a stenotic or malfunctioning valve to contact downstream surfaces of the valve leaflets, and

said proximal portion of said framework comprising a plurality of individually controllable, proximally extending arms which are constructed to swing radially outward at their free ends toward said everted distal arms and contact upstream-facing surfaces of the native leaflets and secure said framework within the human heart valve.

12. The anchoring device according to claim 11 wherein the shape-memory of said central portion of said framework causes it to radially expand while said proximal arms swing outward to contact upstream surfaces of the native leaflets and sandwich the native valve leaflets between them and said everted distal arms so as to provide a secure anchor for a replacement valvular device to be mounted interior thereof.

13. The anchoring device according to claim 12 wherein said central portion is formed with a surface with a shape that is complementary to and that will securely interengage with a portion of a stent for a replacement valvular device having a complementary shape.

14. The anchoring device according to claim 13 wherein said central portion comprises a ring section having a generally annular surface of inwardly convex shape which accommodates string loop means used to control its radial expansion and to collapse said ring section if desired.

15. The anchoring device according to claim 14 wherein an exterior covering of biocompatible sheet material surrounds said framework, and said central portion has the general shape of a section of a torus.

16. The anchoring device according to claim 11 in combination with a hollow delivery implement, wherein the device is disposed about the exterior surface of said hollow implement through which a plurality of cords are routed that individually control the distally-extending and proximally extending arms and control the expansion of the anchoring device as its shape-memory alloy material tends to revert to its desired “

memory”

shape upon warming to body temperature, and wherein a temporary valve element is carried within said hollow delivery implement which valve element can be deployed once said anchoring device is in place so as to serve as a temporary functioning valve.

17. A minimally invasive method for percutaneously implanting a replacement heart valve in the orifice of a native valve within the human heart, which method comprises:

providing an intercostal opening in the chest of the patient and an adjacent opening in the apex of the human heart,

inserting a first catheter through said openings and through a ventricle of the heart to the location of a diseased valve,

deploying a generally tubular anchoring device of shape-memory material from the distal end of said catheter at a location generally interior of the native valve, which device has a plurality of individually controllable distally-extending arms and a plurality of proximally-extending arms,

locating said anchoring device so that, when its shape-memory causes said distally extending arms to evert, said arms each wrap around and about the free ends of the native valve leaflets,

allowing a central portion of the anchoring device to expand to a greater diameter within the orifice of the native valve and said proximally extending arms to swing outward and sandwich the leaflets between these arms and the everted distally extending arms,

removing the first catheter and inserting a second catheter that includes a replacement valvular device that incorporates an expandable stent loaded on a valve delivery implement,

causing said replacement valvular device to be deployed distally from the open distal end of the second catheter,

locating the replacement valvular device interior of said implanted anchoring device and allowing the stent to expand in diameter and mate with said anchoring device, and

withdrawing the catheter and valve delivery implement and closing said openings in said heart and the chest of the patient.

18. The method according to claim 17 wherein a plurality of loops of cord are routed through an anchor delivery implement that is located radially interior of said anchoring device and used to deploy said anchoring device, which cord loops emerge therefrom at longitudinally spaced locations, with separate cord loops being attached to each of said arms and to said radially outwardly expandable anchoring device, which is made of material that is flexible at the temperature being implanted, so as to permit said everted arms, said radially expanded main portion, and said proximally extending arms to be returned toward the initial tubular configuration sufficiently to allow said anchoring device to be relocated/or completely withdrawn should the initial location be other than as exactly desired.

19. The method according to claim 17 wherein said valve delivery implement is located radially interior of said stent and has a plurality of cord loops routed therethrough which emerge at longitudinally spaced locations and are connected to proximal and distal ring portions of the valvular device stent, which cord loops allow said replacement valve device to be reduced in diameter and relocated after first having been mated with said anchoring device or to be completely withdrawn after being returned through the open end of said catheter.

20. The method according to claim 17 for replacement of a stenotic aortic valve wherein said catheter in which said anchoring device is loaded is routed through the left ventricle and into the aortic valve orifice, wherein the anchoring device is carried on a hollow anchoring device delivery implement through which a plurality of cords are routed that individually control the arms and control the expansion of the anchoring device as its shape-memory alloy tends to revert to its desired “

memory”

shape upon warming to body temperature, and wherein a temporary valve element is also carried within said hollow anchoring device delivery implement and is deployed once said anchoring device is in place so as to serve as a functioning aortic valve until said catheter and said delivery implement are withdrawn in preparation for implantation of the replacement valvular device interior of the anchoring device.