Devices and methods for excluding the left atrial appendage
Devices and methods are described for occluding the left atrial appendage (LAA). The device excludes the LAA from blood flow to prevent blood from clotting within the LAA and subsequently embolizing, particularly in patients with atrial fibrillation. The implantable device is delivered via transcatheter delivery into the LAA and secured within the LAA. The implant comprises an expandable and compliant frame and an expandable and conformable tubular foam body. The device may have a thromboresistant cover at a proximal end. The frame may have recapture struts inclining radially outwardly from a central hub. The frame may have axially extending side wall struts, with adjacent pairs of side wall struts joined at one or more apexes. Anchors extend from the frame and into the foam to engage tissue.
1. A left atrial appendage occlusion device, comprising:
a foam body having a tubular sidewall and a closed proximal end, the sidewall defining a longitudinal axis and having a radial uncompressed thickness;
an expandable support coupled with the body; and
at least one anchor coupled with the support and comprising a free end extending radially outwardly and proximally through the sidewall when the foam of the sidewall is compressed in response to radial expansion of the expandable support within the left atrial appendage, wherein the at least one anchor has a radial height no greater than the radial uncompressed thickness of the sidewall.
2. The left atrial appendage occlusion device of claim 1 , wherein the free end extends radially outward in a proximal direction at an angle of at least twenty degrees relative to a portion of the longitudinal axis that extends proximally through the device.
3. The left atrial appendage occlusion device of claim 2 , wherein the angle is at least thirty degrees.
4. The left atrial appendage occlusion device of claim 1 , wherein the free end extends through a radially-compressed portion of the sidewall having a radial thickness less than the radial uncompressed thickness.
5. The left atrial appendage occlusion device of claim 4 , further comprising an attachment that connects the support to the sidewall and radially compresses the sidewall at the radially-compressed portion.
6. The left atrial appendage occlusion device as in claim 1 , wherein the radial uncompressed thickness of the sidewall is at least about 0.5 mm.
7. The left atrial appendage occlusion device as in claim 6 , wherein the radial uncompressed thickness of the sidewall is at least about 1.5 mm).
8. The left atrial appendage occlusion device as in claim 1 , wherein the sidewall extends in a distal direction beyond a distal end of the support by at least about 2 mm in an unconstrained, expanded state.
9. The left atrial appendage occlusion device as in claim 1 , wherein the sidewall comprises a foam having a plurality of interconnected reticulations and voids, and further comprising a PTFE coating on at least some of the interconnected reticulations.
10. The left atrial appendage occlusion device as in claim 1 , comprising a foam proximal end wall.
11. The left atrial appendage occlusion device as in claim 10 , wherein the foam end wall further comprises a cover.
12. The left atrial appendage occlusion device as in claim 11 , wherein the cover comprises ePTFE.
13. The left atrial appendage occlusion device as in claim 1 , wherein the expandable support is self expandable.
14. The left atrial appendage occlusion device as in claim 1 , wherein the expandable support is within a central cavity enclosed by the sidewall.
15. The left atrial appendage occlusion device as in claim 1 , wherein the tubular sidewall has a void content of at least about 90%.
16. The left atrial appendage occlusion device as in claim 1 , wherein the tubular sidewall has an average pore size of at least about 100 microns.
17. The left atrial appendage occlusion device as in claim 1 , wherein the support further comprises at least three recapture struts inclining radially inwardly in a proximal direction to a hub.
18. The left atrial appendage occlusion device as in claim 17 , wherein the support comprises a plurality of axially extending side wall struts, with adjacent pairs of side wall struts joined at an apex.
19. The left atrial appendage occlusion device as in claim 17 , comprising at least six proximally facing apexes and at least six distally facing apexes.
20. The left atrial appendage occlusion device as in claim 17 , wherein each recapture strut is joined to a unique proximally facing apex on the support.
21. The left atrial appendage occlusion device as in claim 20 , wherein the recapture struts are integrally formed with the support.
22. The left atrial appendage occlusion device as in claim 1 , wherein the tubular sidewall comprises a reticulated, cross linked matrix having at least about 90% void content, an average cell size within the range of from about 250-500 microns, a wall thickness of at least about 2 mm and a compressive strength of at least about 1 psi.
23. The left atrial appendage occlusion device of claim 22 , wherein the compressive strength is within a range of from about 1 psi to about 2 psi.
24. A left atrial appendage occlusion device, comprising:
a foam body having a closed proximal end, a distal end and a tubular sidewall that extends circumferentially about a central axis to form a closed cross-section about a cavity, the sidewall comprising at least one first portion having a first radial thickness and at least one second portion having a second radial thickness that is less than the first radial thickness;
an expandable support within the cavity and coupled with the body; and
at least one anchor coupled with the support and comprising a free end extending radially outward and proximally at least partially through the at least one second portion of the sidewall.
25. The left atrial appendage occlusion device of claim 24 , wherein the free end is angled relative to the central axis.
26. The left atrial appendage occlusion device of claim 25 , wherein the free end extends radially outward in a proximal direction at an angle of at least twenty degrees relative to a portion of the central axis that extends proximally to the device.
27. The left atrial appendage occlusion device of claim 26 , wherein the angle is at least thirty degrees.
28. The left atrial appendage occlusion device of claim 25 , wherein the free end extends through the at least one second portion of the sidewall such that a portion of the at least one anchor extends outwardly beyond an outer surface of the at least one second portion of the sidewall.
29. The left atrial appendage occlusion device of claim 25 , wherein the at least one anchor has an axial length that is equal to the first radial thickness.
30. The left atrial appendage occlusion device of claim 24 , wherein the support comprises a tubular frame portion configured to expand radially outward to compress the sidewall against a wall of a left atrial appendage after implantation of the device.
31. The left atrial appendage occlusion device of claim 24 , further comprising a proximal cover that covers at least a portion of a proximal face of the foam body.
32. A left atrial appendage occlusion device, comprising:
a tubular foam body having a closed, proximal circular end;
an expandable support coupled with the foam body, the support comprising a tubular portion having a plurality of struts with pairs of adjacent struts forming proximal and distal apexes; and
an anchor extending from the tubular portion of the support and comprising a tip extending radially outwardly and proximally at least partially into the tubular foam body;
wherein the device is configured to:
insert into a non-cylindrical opening of a rigid test body having a non-cylindrical profile,
expand radially within the non-cylindrical opening, and
conform to the non-cylindrical profile at least at the opening of the test body.
33. The left atrial appendage occlusion device of claim 32 , wherein the foam body includes a compressible side wall extending between a proximal end and a distal end and defines a central cavity.
34. The left atrial appendage occlusion device of claim 33 , wherein the expandable support is configured to compress the side wall against an inner surface of the test body.
35. The left atrial appendage occlusion device of claim 32 , wherein the device after conforming to the non-cylindrical profile leaves no radial gap between the device and the test body having a maximum radial dimension of more than five millimeters.
36. The left atrial appendage occlusion device of claim 35 , wherein the device after conforming to the non-cylindrical profile leaves no radial gap between the device and the test body having a maximum radial dimension of more than three millimeters.
37. The left atrial appendage occlusion device of claim 32 , wherein the tubular foam body comprises a proximal face at the closed circular end and a rounded sidewall extending distally from the proximal face.