Devices and methods for excluding the left atrial appendage
Devices and methods for occluding the left atrial appendage (LAA) to prevent blood from clotting within the LAA and subsequently embolizing, particularly in patients with atrial fibrillation. A foam implant encapsulated with a tough thromboresistent membrane is placed via transvascular means into the LAA and anchored with adhesives and/or mechanical anchors. Tissue over- and in-growth are optimized to anchor the implant in place and provide a permanent occlusion.
1. A left atrial appendage occlusion device, comprising:
an expandable body having an open cell foam proximal, occlusive end for facing a left atrium following implantation of the device in a left atrial appendage, a distal end for facing into the left atrial appendage following implantation of the device in the left atrial appendage, and a cylindrical open cell foam sidewall, wherein the distal end of the expandable body comprises a distal opening for facing into the left atrial appendage following implantation and the open cell foam sidewall forms the distal opening;
a self-expandable stent carried within the expandable body wherein the foam sidewall extends distally linearly beyond the stent at least in a deployed configuration such that following implantation the foam sidewall forms a distal-most end of the device and provides a cushion between the stent and the left atrial appendage, the stent comprising a proximal end positioned within the expandable body distal to the proximal, occlusive end of the expandable body and a plurality of zig-zag struts defining a plurality of apexes including a plurality of distal apexes formed by vertices of adjacent pairs of the zig-zag struts at a distal-most end of the stent; and
a thromboresistent covering on at least a portion of the expandable body.
2. The left atrial appendage occlusion device of claim 1 , wherein the thromboresistent covering comprises a mesh.
3. The left atrial appendage occlusion device of claim 1 , wherein the thromboresistent covering comprises ePTFE.
4. The left atrial appendage occlusion device of claim 1 , wherein the thromboresistent covering is on at least a portion of the proximal end of the expandable body.
5. The left atrial appendage occlusion device of claim 4 , wherein the thromboresistent covering on at least a portion of the proximal end of the expandable body comprises a mesh.
6. The left atrial appendage occlusion device of claim 1 , wherein the stent comprises a plurality of proximal apexes.
7. The left atrial appendage occlusion device of claim 1 , comprising at least one tissue ingrowth surface on the sidewall of the body.
8. The left atrial appendage occlusion device of claim 1 , further comprising a suture releasably attached to the proximal end of the expandable body.
9. The left atrial appendage occlusion device of claim 1 , wherein the expandable body is cylindrical in shape in an unconstrained expansion.
10. The left atrial appendage occlusion device of claim 1 , further comprising at least one anchor.
11. The left atrial appendage occlusion device of claim 10 , wherein the at least one anchor comprises a tissue penetrating element.
12. The left atrial appendage occlusion device of claim 1 , further comprising at least one radiopaque marker.
13. The left atrial appendage occlusion device of claim 12 , wherein the at least one radiopaque marker comprises a radiopaque thread.
14. The left atrial appendage occlusion device of claim 1 , wherein the expandable body comprises polycarbonate-polyurethane urea foam.
15. The left atrial appendage occlusion device of claim 1 , wherein the expandable body can be compressed within a delivery catheter having an inside diameter of no more than about 20F and the expandable body can self-expand to a diameter of at least about 25 mm when released from the delivery catheter.
16. The left atrial appendage occlusion device of claim 1 , wherein the expandable body is coated with a material to enhance thromboresistance.