Tissue fixation devices and methods

1. A tissue gripping device comprising:

a flexible member formed from a shape-memory material, the flexible member comprising a base section and an arm, the arm having a first end connected to the base section, a free end extending away from the base section, and an attachment surface disposed between the first end and the free end;

at least one tissue gripping member formed from a second material, the second material being more rigid than the shape-memory material, the tissue gripping member comprising a mating surface coupled to the attachment surface of the arm to join the tissue gripping member to the flexible member, and a tissue gripping surface disposed opposite the mating surface, the tissue gripping surface including a frictional element configured to resist movement of tissue away from the tissue gripping surface after a tissue has contacted the tissue gripping surface, the frictional element being formed as a plurality of raised barbs disposed along a side edge of the tissue gripping member, and wherein the tissue gripping member includes a plurality of slotted recesses disposed along the side edge at sections adjacent to the raised barbs; and

at least one suture line encircling at least a portion of the tissue gripping member and at least a portion of the arm, the suture line being configured to fasten the tissue gripping member to the arm, the suture line passing through and lodging within one or more of the slotted recesses as it encircles the tissue gripping member and the arm.

2. The tissue gripping device of claim 1 , wherein the shape-memory material is nitinol.

3. The gripping fixation device of claim 1 , wherein the second material is selected from the group consisting of: cobalt-chromium alloy, cobalt-chromium-nickel alloy, cobalt-chromium-nickel-iron-molybdenum-manganese alloy, and stainless steel.

4. The tissue gripping device of claim 1 , wherein the arm further comprises at least one hole, and wherein the tissue gripping member further comprises at least one hole configured to correspond with the hole of the arm as the mating surface of the tissue gripping member is coupled to the attachment surface of the arm.

5. The tissue gripping device of claim 4 , wherein the suture line passes through the hole of the arm and the hole of the tissue gripping member.

6. The tissue fixation device of claim 1 , further comprising a cover, the cover surrounding the arm and the tissue gripping member to hold the tissue gripping member to the flexible member.

7. The tissue fixation device of claim 1 , wherein

the arm further comprises at least one hole and the tissue gripping member further comprises at least one hole configured to correspond with the hole of the arm as the mating surface is coupled to the attachment surface, and

the suture line passing through the hole of the arm and the hole of the tissue gripping member, and

wherein the tissue fixation device further comprises a polymer cover surrounding the arm and the tissue gripping member to hold the tissue gripping member to the flexible member.

8. The tissue fixation device of claim 1 , wherein the arm further comprises a proximal side and a distal side, and wherein the attachment surface is disposed on the distal side.

9. The tissue fixation device of claim 8 , wherein the arm is configured to bend proximally while moving from a relaxed configuration toward a stressed configuration, and to resiliently flex distally toward the relaxed configuration when positioned in the stressed configuration, thereby forcing the attachment surface of the arm against the tissue gripping member as the arm flexes distally toward the relaxed configuration.

10. A tissue fixation system configured for intravascular delivery and for use in joining mitral valve tissue during treatment of the mitral valve, the system comprising:

a body;

a proximal element comprising:

a flexible member formed from a shape-memory material, the flexible member comprising a base section and an arm, the arm having a first end connected to the base section, a free end extending away from the base section, and an attachment surface disposed between the first end and the free end; and

at least one tissue gripping member formed from a second material, the second material being more rigid than the shape-memory material, the tissue gripping member comprising a mating surface coupled to the attachment surface of the arm to join the tissue gripping member to the flexible member, and a tissue gripping surface disposed opposite the mating surface, the tissue gripping surface including a frictional element configured to resist movement of tissue away from the tissue gripping surface after tissue has contacted the tissue gripping surface,

wherein the frictional element is formed as a plurality of raised barbs disposed along a side edge of the tissue gripping member, and

wherein the tissue gripping member includes a plurality of slotted recesses disposed along the side edge at sections adjacent to the raised barbs, and

wherein the arm further comprises at least one hole and the tissue gripping member further comprises at least one hole configured to correspond with the hole of the arm as the mating surface of the tissue gripping member is coupled to the attachment surface of the arm, and

the proximal element further comprising at least one suture line encircling the tissue gripping member and the arm, the suture line passing through the hole of the arm and the hole of the tissue gripping member and passing through and lodging within one or more of the slotted recesses; and

a distal element having a first end pivotally coupled to the body and extending to a free second end and a tissue engagement surface between the first and second end, the tissue engagement surface being configured to approximate and engage a portion of the leaflets of the mitral valve, wherein the proximal element is configured to cooperate with the distal element to form a space for receiving a portion of mitral valve tissue therebetween.

11. The system of claim 10 , wherein the shape-memory material is nitinol and the second material is a cobalt-chromium-nickel-iron-molybdenum-manganese alloy.

12. A tissue gripping device comprising:

a flexible member formed from a shape-memory material, the flexible member comprising a base section and an arm, the arm having a first end connected to the base section, a free end extending away from the base section, and an attachment surface disposed between the first end and the free end;

at least one tissue gripping member formed from a second material, the second material being more rigid than the shape-memory material, the tissue gripping member comprising a mating surface coupled to the attachment surface of the arm to join the tissue gripping member to the flexible member, and a tissue gripping surface disposed opposite the mating surface, the tissue gripping surface including a frictional element configured to resist movement of tissue away from the tissue gripping surface after tissue has contacted the tissue gripping surface; and

a suture line configured to fasten the tissue gripping member to the arm,

wherein the arm further comprises at least one hole, and wherein the tissue gripping member further comprises at least one hole configured to correspond with the hole of the arm as the mating surface of the tissue gripping member is coupled to the attachment surface of the arm, and

wherein the suture line passes through the hole of the arm and the hole of the tissue gripping member.

13. The tissue fixation device of claim 12 , further comprising a cover, the cover surrounding the arm and the tissue gripping member to hold the tissue gripping member to the flexible member.

14. The tissue gripping device of claim 12 , wherein the shape-memory material is nitinol.

15. The gripping fixation device of claim 12 , wherein the second material is selected from the group consisting of: cobalt-chromium alloy, cobalt-chromium-nickel alloy, cobalt-chromium-nickel-iron-molybdenum-manganese alloy, and stainless steel.

16. The tissue fixation device of claim 12 , wherein the arm further comprises a proximal side and a distal side, and wherein the attachment surface is disposed on the distal side.

17. The tissue fixation device of claim 16 , wherein the arm is configured to bend proximally while moving from a relaxed configuration toward a stressed configuration, and to resiliently flex distally toward the relaxed configuration when positioned in the stressed configuration, thereby forcing the attachment surface of the arm against the tissue gripping member as the arm flexes distally toward the relaxed configuration.