Prosthetic heart valves

Abstract

A prosthetic heart valve (e.g., a prosthetic aortic valve) is designed to be somewhat circumferentially collapsible and then re-expandable. The collapsed condition may be used for less invasive delivery of the valve into a patient. When the valve reaches the implant site in the patient, it re-expands to normal operating size, and also to engage surrounding tissue of the patient. The valve includes a stent portion and a ring portion that is substantially concentric with the stent portion but downstream from the stent portion in the direction of blood flow through the implanted valve. When the valve is implanted, the stent portion engages the patient's tissue at or near the native valve annulus, while the ring portion engages tissue downstream from the native valve site (e.g., the aorta).

1 - 31 . (canceled) 
     
     
         32 . A prosthetic heart valve, comprising:
 a collapsible and expandable stent having a proximal end, a distal end, an annulus section adjacent the proximal end and an aortic section adjacent the distal end, the stent having a first convex curvature and a second concave curvature proximal to the first curvature;   a collapsible and expandable valve assembly disposed within the stent and including a plurality of leaflets; and   a cuff annularly disposed about the valve assembly in the annulus section.   
     
     
         33 . The prosthetic heart valve of  claim 32 , wherein the annulus portion includes a lower skirt adjacent the proximal end, and the second concave curvature is at least partially defined by the lower skirt. 
     
     
         34 . The prosthetic heart valve of  claim 33 , wherein lower skirt extends radially outward. 
     
     
         35 . The prosthetic heart valve of  claim 33 , wherein the lower skirt is configured and arranged to complement a shape of a native valve annulus. 
     
     
         36 . The prosthetic heart valve of  claim 32 , wherein the first and second curvatures on the stent are smooth and define a partially sinusoidal profile. 
     
     
         37 . The prosthetic heart valve of  claim 33 , wherein the lower skirt has a constant curvature around the circumference of the stent. 
     
     
         38 . The prosthetic heart valve of  claim 33 , wherein the lower skirt has a variable curvature around the circumference of the stent. 
     
     
         39 . The prosthetic heart valve of  claim 33 , wherein the lower skirt has a scalloped free edge. 
     
     
         40 . The prosthetic heart valve of  claim 33 , wherein a diameter of the lower skirt decreases from the proximal end of the stent toward the distal end of the stent. 
     
     
         41 . The prosthetic heart valve of  claim 33 , wherein a diameter of the lower skirt at the proximal end of the stent is the largest diameter of the stent along a length of the stent. 
     
     
         42 . The prosthetic heart valve of  claim 33 , wherein the lower skirt is configured to apply a force to a bottom of a native valve annulus when implanted. 
     
     
         43 . The prosthetic heart valve of  claim 33 , wherein the lower skirt is configured and arranged to conform to a curvature of a bottom of a native valve annulus to reduce paravalvular leakage. 
     
     
         44 . The prosthetic heart valve of  claim 32 , wherein the plurality of leaflets includes three leaflets. 
     
     
         45 . The prosthetic heart valve of  claim 32 , wherein the plurality of leaflets includes tissue. 
     
     
         46 . The prosthetic heart valve of  claim 32 , wherein a first portion of the stent is more resistant to annular compression than a second portion of the stent. 
     
     
         47 . A prosthetic heart valve, comprising:
 a collapsible and expandable stent having a proximal end, a distal end, an annulus section adjacent the proximal end and an aortic section adjacent the distal end, the stent having a concave lower skirt portion in the annulus section that deflects radially outwardly at the proximal end;   a collapsible and expandable valve assembly disposed within the stent and including a plurality of leaflets; and   a cuff annularly disposed about the valve assembly in the annulus section.   
     
     
         48 . A prosthetic heart valve, comprising:
 a collapsible and expandable stent having a proximal end, a distal end, and an annulus section adjacent the proximal end;   a collapsible and expandable valve assembly disposed within the stent and including a plurality of leaflets; and   at least two layers material annularly disposed on the valve assembly in the annulus section adjacent the proximal end of the stent, the at least two layers at least partially overlapping one another.   
     
     
         49 . The prosthetic heart valve of  claim 48 , wherein the at least two layers include a first layer disposed on a luminal surface of the stent, and a second layer disposed on an abluminal surface of the stent. 
     
     
         50 . The prosthetic heart valve of  claim 49 , wherein the first layer and the second layer are continuous with one another. 
     
     
         51 . The prosthetic heart valve of  claim 49 , wherein the first layer and the second layer are formed of a single web of material that is folded at a fold line corresponding to a bottom edge of the stent adjacent the proximal end. 
     
     
         52 . The prosthetic heart valve of  claim 49 , wherein the first layer extends a first distance from a bottom edge of the stent toward the distal end of the stent and the second layer extends a second distance from the bottom edge of the stent toward the distal end of the stent, the first distance and the second distance being equal. 
     
     
         53 . The prosthetic heart valve of  claim 49 , wherein the first layer extends a first distance from a bottom edge of the stent toward the distal end of the stent and the second layer extends a second distance from the bottom edge of the stent toward the distal end of the stent, the first distance and the second distance being unequal. 
     
     
         54 . The prosthetic heart valve of  claim 49 , wherein the first layer extends a first distance from a bottom edge of the stent toward the distal end of the stent and the second layer extends a second distance from the bottom edge of the stent toward the distal end of the stent, the first distance being greater than the second distance. 
     
     
         55 . The prosthetic heart valve of  claim 49 , wherein the first layer and the second layer include at least two different materials. 
     
     
         56 . The prosthetic heart valve of  claim 49 , wherein at least one of the first layer and the second layer includes a fabric. 
     
     
         57 . The prosthetic heart valve of  claim 49 , wherein at least one of the first layer and the second layer includes at least one of Dacron, polyester or Teflon. 
     
     
         58 . The prosthetic heart valve of  claim 49 , wherein at least one of the first layer and the second layer includes a material selected to promote tissue in-growth. 
     
     
         59 . The prosthetic heart valve of  claim 49 , wherein at least one of the first layer and the second layer includes tissue. 
     
     
         60 . The prosthetic heart valve of  claim 48 , wherein the at least two layers include a fabric layer and a tissue layer. 
     
     
         61 . The prosthetic heart valve of  claim 49 , wherein the stent includes a plurality of cells arranged in annular rows around the stent and the second layer extends over at least one full row of the cells. 
     
     
         62 . The prosthetic heart valve of  claim 49 , wherein the stent includes a plurality of cells arranged in annular rows around the stent and the second layer extends over at least a portion of one of the rows of the cells.