Valve prosthesis

Abstract

The present disclosure relates to valve replacement devices that are foldable for catheter-based deployment to the site of implantation, as well as systems for the delivery of valve prostheses, including prostheses having the special characteristics of the disclosed valve replacement devices. The devices include highly effective adhering mechanisms for secure and enduring precision implantation. The adhering mechanisms may employ a unique sealing mechanism that includes a cuff that expands slowly whereby the device is not secured in place until the completion of the implantation procedure. The implanted device, optionally together with the cuff, prevents perivalvular leaks and incorporate an appropriate leaflet system for reliable functioning in situ.

1 .- 24 . (canceled) 
     
     
         25 . A vascular reducer comprising:
 a stent-based platform adapted for percutaneous delivery and anchoring in a heart valve annulus, said stent-based platform comprising an at least partially self-expanding stent and a cuff comprising an absorbent material disposed at least partially circumferentially around the outer and inner surface of said at least partially self-expanding stent, wherein said absorbent material expands by absorption of a fluid to substantially seal said at least partially self-expanding stent at an implantation site, and wherein said expansion of said absorbent material is delayed for a time sufficient to permit positioning of said at least partially self-expanding stent at said implantation site; and   a valved-stent prosthetic device adapted to be percutaneously delivered to the heart valve annulus for mounting in said stent-based platform.   
     
     
         26 . The vascular reducer according to  claim 25 , wherein the stent-based platform is adapted for anchoring in a pulmonary valve annulus and the valved-stent prosthetic device comprises a pulmonary valved-stent prosthetic device adapted for delivery to the pulmonary valve annulus. 
     
     
         27 . The vascular reducer according to  claim 25 , wherein the stent-based platform is adapted for anchoring in a tricuspid valve annulus and the valved-stent prosthetic device comprises a tricuspid valved-stent prosthetic device adapted for delivery to the tricuspid valve annulus. 
     
     
         28 . The vascular reducer according to  claim 25 , wherein the absorbent material is implemented as a bi-layer system in which an outer layer is a fluid impermeable material that prevents the absorbent material from expanding while the at least partially self-expanding stent is being placed, said outer layer adapted to elute off to allow the underlying absorbent material to expand to permit positioning of said at least partially self-expanding stent. 
     
     
         29 . The vascular reducer according to  claim 28 , wherein the absorbent material is a crosslinked hydrogel comprising poly(acrylic acid) and a poly(ethylene glycol). 
     
     
         30 . The vascular reducer according to  28 , wherein the fluid impermeable material comprises a fluid impermeable polymer barrier deposited on the absorbent material. 
     
     
         31 . A vascular reducer comprising:
 a stent-based platform adapted for percutaneous delivery and anchoring in a heart valve annulus, said stent-based platform comprising an at least partially self-expanding stent and a cuff comprising an absorbent material that is a crosslinked hydrogel comprising poly(acrylic acid) and a poly(ethylene glycol) that disposed at least partially circumferentially around the outer surface of said at least partially self-expanding stent, wherein said absorbent material expands by absorption of a fluid to substantially seal said at least partially self-expanding stent at an implantation site, and wherein said expansion of said absorbent material is delayed for a time sufficient to permit positioning of said at least partially self-expanding stent at said implantation site; and   a valved-stent prosthetic device adapted to be percutaneously delivered to the heart valve annulus for mounting in said stent-based platform.   
     
     
         32 . The vascular reducer according to  claim 31 , wherein the stent-based platform is adapted for anchoring in a pulmonary valve annulus and the valved-stent prosthetic device comprises a pulmonary valved-stent prosthetic device adapted for delivery to the pulmonary valve annulus. 
     
     
         33 . The vascular reducer according to  claim 31 , wherein the stent-based platform is adapted for anchoring in a tricuspid valve annulus and the valved-stent prosthetic device comprises a tricuspid valved-stent prosthetic device adapted for delivery to the tricuspid valve annulus. 
     
     
         34 . The vascular reducer according to  claim 31 , wherein the absorbent material is implemented as a bi-layer system in which an outer layer is a fluid impermeable material that prevents the absorbent material from expanding while the at least partially self-expanding stent is being placed, said outer layer adapted to elute off to allow the underlying absorbent material to expand to permit positioning of said at least partially self-expanding stent. 
     
     
         35 . The vascular reducer according to  claim 34 , wherein the fluid impermeable polymer is deposited on the absorbent material.