Valve Prosthesis

A prosthetic device comprising:

• an at least partially self-expanding stent adapted for percutaneous delivery and anchoring in a mitral valve annulus, said stent comprising
• an expanded and an unexpanded state;
• a middle region having first and second ends and comprising a framework that defines inner and outer surfaces;
• a lower flange portion at the first end of the middle region that comprises a plurality of flange elements, each of said elements having a first end that is attached to the middle region and an opposed second end that is spaced from the first end;
• an upper flange portion at the second end of the middle region that comprises a plurality of flange elements, each of said elements having a first end that is attached to the middle region and an opposed second end that is spaced from the first end;
• wherein,
• when said stent is in the unexpanded state, the upper and lower flange portions are oriented substantially along the long axis of the stent;
• when said stent transitions from the unexpanded state to the expanded state, the lower flange portion transitions in space so that it is no longer oriented substantially along the long axis of the stent;
• the lower flange portion is adapted to anchor the stent within the mitral annulus by grasping tissue at the ventricular side of the annulus by enfolding it between the lower flange portion and the outer surface of the middle region as the stent transitions from the unexpanded state to the expanded state;
• and, the upper flange portion is adapted to anchor the stent within the mitral annulus by grasping tissue between the upper flange portion and the outer surface of the middle region and
• a cuff comprising an absorbent material that is a crosslinked hydrogel comprising poly(acrylic acid) and a poly(ethylene glycol) that is disposed at least partially circumferentially around an 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 valve comprising at least one leaflet fixedly attached to an interior surface of the stent.