Devices and methods for the treatment of vascular defects
Devices and methods for treating vascular defects, such as, for example, balloon-type aneurysms, are described herein. In one embodiment, an apparatus includes an insertion portion and an expandable implant. The expandable implant is configured to be deployed in an aneurysm and is coupled to the insertion portion. The expandable implant has a first portion and a second portion coupled to the first portion. The expandable implant is movable between a first configuration in which the first portion and the second portion are substantially linearly aligned and a second configuration in which the second portion at least partially overlaps the first portion.
1. An expandable implant configured to be positioned within an aneurysm, the implant comprising:
a first braid having a collapsed configuration and an expanded configuration, wherein in the collapsed configuration the first braid is configured to be contained in a delivery device and in the expanded configuration the first braid has a plurality of petal-shaped portions;
a second braid having a collapsed configuration and an expanded configuration, wherein, in the collapsed configuration, the second braid is configured to be contained in a delivery device and the second braid is positioned along a central longitudinal axis of the implant at a location that is proximate the first braids,
wherein at least one of the first braid and the second braid is a flattened tubular braid, and
wherein, in the expanded configuration—
the petal-shaped portions of the first braid are configured to contact and conform to an inner surface of the aneurysm thereby forming a spherical layer; and
the second braid is positioned within an interior volume defined by the spherical layer.
2. The implant of claim 1 wherein the spherical layer is a first spherical layer and wherein the second braid forms a second spherical layer in the expanded configuration and an average width of the first spherical layer is greater than an average width of the second spherical layer.
3. The implant of claim 1 wherein an average stiffness of the first braid is greater than an average stiffness of the second braid.
4. The implant of claim 1 wherein the petal-shaped portions are first petal-shaped portions, and wherein the second braid includes a plurality of second petal-shaped portions in the expanded configuration.
5. The implant of claim 4 wherein an average width of the first petal-shaped portions is greater than an average width of the second petal-shaped portions.
6. The implant of claim 4 wherein the first braid has more first petal-shaped portions than the second braid has second petal-shaped portions.
7. The implant of claim 4 wherein an average length of the first petal-shaped portions is greater than an average length of the second petal-shaped portions.
8. The implant of claim 4 wherein an average stiffness of the petal-shaped portions of the first braid is greater than an average stiffness of the petal-shaped portions of the second braid.
9. The implant of claim 1 wherein the first braid and the second braid are discrete, separate braids, and wherein the implant further includes a coupler positioned between and coupled to the first and second braids.
10. The implant of claim 1 wherein the first braid and the second braid are discrete, separate braids, and wherein the implant further includes a flexible elongated member extending through the first braid and the second braid, thereby mechanically coupling the first braid to the second braid.
11. The implant of claim 1 wherein a proximal portion of the second braid is configured to be releasably coupled to a delivery device.
12. The implant of claim 1 , further including a flexible member configured to extend distally from the distal portion of the first braid and configured to have a curved shape in a non-constrained configuration.
13. The implant of claim 1 wherein the petal-shaped portions are first petal-shaped portions, the second braid includes a plurality of second petal-shaped portions in the expanded configuration, and the spherical layer is a first spherical layer, and wherein the implant further comprises a third braid having a collapsed configuration and an expanded configuration, wherein—
the third braid is positioned along the central longitudinal axis of the implant at a location that is proximate the second braid; and
wherein, in the expanded configuration—
the second petal-shaped portions are configured to contact and conform to an inner surface of the first spherical layer thereby forming a second spherical layer within the first spherical layer; and
the third braid is positioned within an interior volume defined by the second spherical layer.
14. The implant of claim 1 wherein the second braid is a tubular braid configured to form a three-dimensional structure in the expanded configuration.