Valve Prosthesis Fixation Techniques Using Sandwiching

• US 20120046742A1
• Filed: 10/31/2011
• Published: 02/23/2012
• Est. Priority Date: 09/19/2006
• Status: Active Grant

• Current Assignee: Medtronic Ventor Technologies LTD. (Medtronic Plc)
• Original Assignee: Medtronic Ventor Technologies LTD. (Medtronic Plc)
• Inventors: TUVAL, YOSI, KILEMNIK, IDO, BENARY, RAPHAEL
• Granted Patent: US 8,771,345 B2
• Time in Patent Office: Days
• US Class Current: 623/2.18
• 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 2/2427 Devices for manipulating or deploying heart valves during implantation
• CPC Class Codes: A61F 2/2436 Deployment by retracting a sheath
• CPC Class Codes: A61F 2/2469 with resilient valve members, e.g. conical spiral
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• 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 2230/0006 circular
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2230/0071 spherical
• CPC Class Codes: A61F 2230/008 paraboloidal
• CPC Class Codes: A61F 2250/0039 differing in diameter

Abstract

A prosthesis including a distal fixation member that defines two or more engagement arms that are configured to apply a first axial force to tissue of the subject on a downstream side of the native valve complex. The prosthesis also includes a proximal fixation member configured to apply a second axial force to tissue of the subject on an upstream side of the native valve complex such that application of the first and second axial forces couples the prosthesis to the native valve complex. The proximal fixation member and the distal fixation member are fabricated as one integrated structure. The engagement arms and the proximal fixation member are configured to capture leaflets of the native valve complex therebetween without folding over of leaflets of the native valve complex, upon implantation of the prosthesis.

Claims

1-188. -188. (canceled)

189. A prosthesis for implantation at a native valve complex of a subject, the prosthesis comprising:

a distal fixation member, configured to be positioned downstream of the native valve complex, and shaped so as to define two or more engagement arms that are configured to apply a first axial force to tissue of the subject on a downstream side of the native valve complex; and

a proximal fixation member coupled to the distal fixation member, the proximal fixation member configured to be positioned at least partially on an upstream side of the native valve complex, and to apply a second axial_force to tissue of the subject on an upstream side of the native valve complex, such that application of the first and second axial forces couples the prosthesis to the native valve complex,

wherein the proximal fixation member and the distal fixation member are fabricated as one integrated structure, and

wherein the engagement arms and the proximal fixation member are configured to capture leaflets of the native valve complex therebetween without folding over leaflets of the native valve complex, upon implantation of the prosthesis.

190. The prosthesis according to claim 189, wherein the engagement arms comprise portions of the structure that are bent proximally.

191. The prosthesis according to claim 189, wherein the engagement arms and the proximal fixation member are configured to couple the prosthesis to the native valve complex by axially sandwiching the native valve complex from a downstream side and the upstream side thereof, upon implantation of the prosthesis.

192. The prosthesis according to claim 189, wherein the distal fixation member does not press upon the native commissures upon implantation of the prosthesis.

193. The prosthesis according to claim 189, wherein the prosthesis is configured, upon implantation thereof, to embrace, without squeezing, leaflets of the native valve complex.

194. The prosthesis according to claim 189, wherein the engagement arms meet one another at junctures, wherein the engagement arms are shaped so as define three peak complexes at the junctures, and trough complexes, each of which is between the peak complexes, and wherein, upon implantation of the prosthesis, at least a portion of each of the peak complexes is disposed distal to and in rotational alignment with a respective one of native commissures of the native valve complex.

195. The prosthesis according to claim 189, wherein the prosthesis comprises a prosthetic valve having one or more prosthetic leaflets, and wherein the prosthetic valve is coupled to the prosthesis such that at least 50% of an axial length of the prosthetic leaflets is distal to native valve leaflets of the native valve complex upon implantation of the prosthesis.

196. The prosthesis according to claim 189, wherein the proximal fixation member comprises an inner support structure, and wherein the distal fixation member comprises an outer support structure that is disposed partially over the inner support structure.

197. The prosthesis according to claim 196, wherein the inner support structure is shaped so as to define a bulging proximal skirt, a proximal portion of which is configured to apply the second axial force.

198. The prosthesis according to claim 196, wherein a proximal portion of the inner support structure is wider than a distal portion of the inner support structure.

199. The prosthesis according to claim 189, wherein:

the first axial force is directed upstream; and

the second axial force is directed downstream.

200. The prosthesis according to claim 189, wherein the prosthesis is configured to apply the first axial force such that a ratio of (a) the first axial force to (b) a radial force applied outwardly by the prosthesis against the native valve complex is greater than 1.5:

1.

201. The prosthesis according to claim 189, wherein the prosthesis is configured to apply the first axial force with a force of at least 40 g.

202. The prosthesis according to claim 189, wherein the prosthesis is configured such that any radial force applied by the prosthesis outwardly against the native valve complex is insufficient by itself to chronically maintain the prosthesis in position with respect to the native valve complex under conditions of normal cardiac motion.

203. The prosthesis according to claim 189, wherein the prosthesis is configured to apply a radial force of less than 0.5 pounds outwardly against the native valve complex.

204. The prosthesis according to claim 203, wherein the prosthesis is configured to apply a radial force of less than 0.3 pounds outwardly against the native valve complex.

205. The prosthesis according to claim 204, wherein the prosthesis is configured to apply a radial force of less than 0.1 pounds outwardly against the native valve complex.

206. The prosthesis according to claim 189, wherein the native valve complex is a mitral valve complex.

207. A method for implanting a valve prosthesis at a native valve complex of a subject, the method comprising:

positioning a distal fixation member of the valve prosthesis downstream of the native valve complex, the distal fixation member defining two or more engagement arms, the distal fixation member being positioned downstream such that the engagement arms apply a first axial force to tissue of the subject on a downstream side of the native valve complex; and

positioning a proximal fixation member of the valve prosthesis at least partially upstream of the native valve complex, the proximal fixation member being fabricated as one integrated structure with the distal fixation member, the proximal fixation member being positioned such that the proximal fixation member applies a second axial force to tissue of the subject on an upstream side of the native valve complex,

wherein the positioning the proximal and distal fixation members comprises capturing leaflets of the native valve complex between the proximal fixation member and the engagement arms without folding over leaflets of the native valve complex,

wherein application of the first and second axial forces couples the prosthesis to the native valve complex.

208. The method according to claim 207, wherein the engagement arms are bent proximally.

209. The method according to claim 207, wherein positioning the distal fixation member comprises positioning the distal fixation member downstream of the native valve complex, such that the engagement arms apply the first axial force in an upstream direction, and wherein positioning the proximal fixation member comprises positioning the proximal fixation member such that the proximal fixation member applies the second axial force in a downstream direction.

210. The method according to claim 207, wherein positioning the distal and proximal fixation members comprises positioning the distal fixation member downstream of the native valve complex before positioning the proximal fixation member at least partially upstream of the native valve complex.

211. The method according to claim 207, wherein positioning the distal fixation member comprises positioning the distal fixation member such that it limits an extent of opening of leaflets of the native valve complex.

212. The method according to claim 207, wherein positioning the proximal and distal fixation members comprises:

collapsing the proximal and distal fixation members;

inserting the proximal and distal fixation members, while collapsed, upstream and downstream of the valve complex, respectively; and

expanding the proximal and distal fixation members upstream and downstream of the valve complex, respectively.

213. The method according to claim 212, wherein positioning the distal fixation member comprises positioning the distal fixation member downstream of the valve complex while collapsed, and expanding the distal fixation member before positioning the proximal fixation member at least partially upstream of the native valve complex.

214. The method according to claim 212, wherein inserting the proximal and distal fixation members comprises storing the proximal and distal fixation members while collapsed in at least one tube selected from the group consisting of:

an overtube and a trocar, and wherein expanding the proximal and distal fixation members comprises deploying the proximal and distal fixation members from the selected tube.

215. The method according to claim 214, wherein inserting the proximal and distal fixation members comprises inserting the selected tube through an apex of a heart of the subject, and advancing the selected tube through the ventricle until a distal end of the selected tube passes the native valve complex.

216. The method according to claim 214, wherein inserting the proximal and distal fixation members comprises inserting the selected tube using a transaortic approach.

217. The method according to claim 207, wherein:

the proximal fixation member includes an inner support structure;

the distal fixation member includes an outer support structure that is placed partially over the inner support structure; and

positioning the proximal and distal fixation members comprises positioning the inner and outer support structures, respectively.

218. The method according to claim 217, wherein:

the inner support structure is shaped so as to define a bulging proximal skirt; and

positioning the proximal fixation member comprises positioning the inner support structure such that a proximal portion of the bulging proximal skirt applies the second axial force.

219. The method according to claim 217, wherein:

a proximal portion of the inner support structure is wider than a distal portion of the inner support structure; and

positioning the proximal fixation member comprises positioning the inner support structure such that the proximal portion of the inner support structure applies the second axial force.

220. The method according to claim 217, wherein:

the outer support structure is shaped so as to define a plurality of distal diverging strut supports from which the engagement arms extend radially outward; and

positioning the distal fixation member comprises positioning the outer support structure that defines the plurality of distal diverging strut supports.

221. The method according to claim 207, wherein the native valve complex is a mitral valve complex.