Prosthetic valve with atrial tissue anchors having variable flexibility and ventricular tissue anchors having constant flexibility

1. An expandable prosthetic valve for implantation within a native heart valve, the prosthetic valve configured to have a contracted configuration and an expanded configuration, the prosthetic valve comprising:

an annular valve body;

a plurality of atrial anchoring arms configured to extend radially outward from the annular valve body, each atrial anchoring arm having a proximal arm end and a distal arm end, wherein at least one of the plurality of atrial anchoring arms comprises:

a proximal portion,

a flexible distal portion situated between the proximal portion and the distal arm end of the at least one atrial anchoring arm, and

a tissue grasping feature situated at a distal end of the proximal portion, the tissue grasping feature being the portion of the proximal portion with the largest width; and

a plurality of ventricular anchoring legs configured to extend radially outward from the annular valve body, each ventricular anchoring leg having a proximal leg end and a distal leg end, wherein each of the ventricular anchoring legs has a substantially constant flexibility from the proximal leg end to the distal leg end; and

an annular outer frame;

wherein, when the prosthetic valve is in the expanded configuration, the tissue grasping feature of the proximal portion of the at least one atrial anchoring arm is positioned the same distance from a center of the annular valve as the distal leg end of at least one of the ventricular anchoring legs;

further wherein a connector pin is situated at an intersection of at least one venticular anchoring leg and two adjacent struts of the annular outer frame.

2. The prosthetic valve of claim 1 , wherein the flexibility of the at least one atrial anchoring arm increases from the proximal arm end of the at least one atrial anchoring arm to the distal arm end of the at least one atrial anchoring arm.

3. The prosthetic valve of claim 1 , wherein the flexible distal portion of the at least one atrial anchoring arm includes a structure having multiple curves.

4. The prosthetic valve of claim 3 , wherein the structure having multiple curves includes a serpentine pattern.

5. The prosthetic valve of claim 3 , wherein the at least one atrial anchoring arm includes a transition location and the structure having multiple curves is situated distal to the transition location.

6. The prosthetic valve of claim 3 , wherein the structure having multiple curves does not extend to the distal arm end of the at least one atrial anchoring arm.

7. The prosthetic valve of claim 3 , wherein the inflexible proximal portion of the at least one atrial anchoring arm is positioned proximal to the structure having multiple curves.

8. The prosthetic valve of claim 7 , wherein a cross-sectional area of the structure having multiple curves is smaller than a cross-sectional area of the inflexible proximal portion of the at least one atrial anchoring arm.

9. The prosthetic valve of claim 7 , wherein the tissue grasping feature of the at least one atrial anchoring arm comprises an opening.

10. The prosthetic valve of claim 9 ,

wherein the at least one ventricular anchoring leg includes an opening, and

wherein the opening of the tissue grasping feature and the opening of the at least one ventricular anchoring leg are substantially equidistant from the center of the annular valve body.

11. The prosthetic valve of claim 1 , wherein the at least one atrial anchoring arm includes a transition location and is configured for greater flexibility distal the transition location than proximal the transition location.

12. The prosthetic valve of claim 11 , wherein the at least one atrial anchoring arm distal the transition location has a cross-sectional area smaller than a cross-sectional area of the at least one atrial anchoring arm proximal the transition location.

13. The prosthetic valve of claim 11 , wherein the at least one atrial anchoring arm distal the transition location is more flexible than the at least one ventricular anchoring leg.

14. The prosthetic valve of claim 1 , wherein the distal arm end of the at least one atrial anchoring arm comprises an opening.

15. The prosthetic valve of claim 1 , wherein each atrial anchoring arm and each ventricular anchoring leg has a single location of connection to the annular valve body.

16. The prosthetic valve of claim 1 , wherein radially external to the locations of connection between the atrial anchoring arms and the annular valve body, no connection is made between the plurality of atrial anchoring arms.

17. The prosthetic valve of claim 1 , wherein the at least one atrial anchoring arm is configured to extend radially outward beyond the distal leg end of the at least one ventricular anchoring leg.

18. The prosthetic valve of claim 1 , wherein each of the plurality of ventricular anchoring legs has substantially the same flexibility.

19. The prosthetic valve of claim 1 , wherein the annular valve body comprises:

an annular outer frame; and

an inner frame configured at least partially within the annular outer frame.

20. The prosthetic valve of claim 19 , wherein the plurality of atrial anchoring arms is configured to extend from the inner frame and the plurality of ventricular anchoring legs is configured to extend from the annular outer frame.

21. The prosthetic valve of claim 1 , wherein the proximal leg end of the at least one of the plurality of ventricular anchoring legs includes an attachment location for joining a first and second portion of the annular valve body.