Multi-lumen stent-graft and related surgical methods
A multi-lumen stent-graft including a graft portion and a stent frame. The stent-graft includes multiple through-channels formed of the graft portion. The graft portion can comprise a PTFE material and the through-channels can be formed of fused portions of the graft portion. The stent-graft can be used in a prostheses that connects multiple vessel branches such as for the repair of aortic aneurysms or other vessels of the body.
1 . An expandable stent-graft comprising:
a graft sleeve comprising Polytetrafluoroethylene (PTFE) material, the graft sleeve comprising:
a main fluid flow channel extending from a first cylindrical opening at a first end of the graft sleeve to a second cylindrical opening at a second end of the graft sleeve, the second end opposite the first end; and
a central portion between the first cylindrical opening and the second cylindrical opening along a longitudinal axis of the graft sleeve, the central portion comprising:
a first internal flow channel and a second internal flow channel, both the first internal flow channel and the second internal flow channel in fluid communication with the main fluid flow channel, each of the first internal flow channel and the second internal flow channel including an inlet port and an outlet port recessed inwardly in a longitudinal direction from the first cylindrical opening and the second cylindrical opening respectively along the longitudinal axis of the graft sleeve,
wherein a longitudinal axis of the first internal flow channel is offset from a longitudinal axis of the second internal flow channel, the first internal flow channel defining a separate fluid flow path through the central portion from the second internal flow channel; and
a self-expanding wire stent coaxially mounted over the graft sleeve and affixed to said graft sleeve at the first cylindrical opening and the second cylindrical opening, wherein the central portion is unsupported by and spaced radially inwardly relative to the self-expanding wire stent.
2 . The expandable stent-graft of claim 1 , wherein a channel length of the first internal flow channel and the second internal flow channel is between 50% and 90% of a hub length extending from an upper rim of the first cylindrical opening to a lower rim of the second cylindrical opening.
3 . The expandable stent-graft of claim 1 , wherein a channel length of the first internal flow channel and the second internal flow channel is between 75% and 90% of a hub length extending from an upper rim of the first cylindrical opening to a lower rim of the second cylindrical opening.
4 . The expandable stent-graft of claim 1 , further comprising a first cylindrical wall portion defining the first cylindrical opening and a second cylindrical wall portion defining the second cylindrical opening, wherein the first cylindrical wall portion and the second cylindrical wall portion are supported by the self-expanding wire stent, and wherein the inlet ports and the outlet ports are spaced axially inwardly and radially inwardly from the first cylindrical wall portion and the second cylindrical wall portion respectively.
5 . The expandable stent-graft of claim 4 , wherein the first cylindrical wall portion and the second cylindrical wall portion include folded portions of the PTFE material.
6 . The expandable stent-graft of claim 1 , wherein the first internal flow channel and the second internal flow channel are separated by a linear connected segment aligned along the longitudinal axis.
7 . The expandable stent-graft of claim 6 , wherein the linear connected segment is formed of fused portions of an internal surface of the PTFE material of the graft sleeve, wherein the fused portions of the internal surface of the PTFE material are formed by melting the PTFE material above a melting temperature thereof.
8 . The expandable stent-graft of claim 7 , wherein both the first internal flow channel and the second internal flow channel have a smaller diameter than the main fluid flow channel.
9 . The expandable stent-graft of claim 1 , wherein the graft sleeve comprises a single tube of PTFE material and a total circumference of each of the first internal flow channel and the second internal flow channel is equal to a circumference of the single tube of polymer material.
10 . An expandable stent-graft comprising:
a graft portion comprising:
a first cylindrical wall at a first end of the expandable stent-graft;
a second cylindrical wall at a second end of the expandable stent-graft;
a first internal wall recessed inwardly along a longitudinal axis of the expandable stent-graft from the first end;
a second internal wall recessed inwardly along the longitudinal axis from the second end, the first internal wall and the second internal wall being orthogonal to the longitudinal axis;
a main fluid flow channel extending between the first end and the first internal wall and defined by the first cylindrical wall, the main fluid flow channel further extending between the second internal wall and the second end and defined by the second cylindrical wall;
a first internal flow channel in fluid communication with the main fluid flow channel, the first internal flow channel comprising a first inlet port in the first internal wall and a first outlet port in the second internal wall; and
a second internal flow channel in fluid communication with the main fluid flow channel, the second internal flow channel comprising a second inlet port in the first internal wall and a second outlet port in the second internal wall; and
a self-expanding wire stent coaxially mounted over the graft portion, the self-expanding wire stent coupled to the graft portion at the first cylindrical wall and the second cylindrical wall.
11 . The expandable stent-graft of claim 10 , wherein the first internal flow channel and the second internal flow channel are separated by a linear connected segment aligned with the longitudinal axis.
12 . The expandable stent-graft of claim 11 , wherein the linear connected segment comprises one or more fused portions of a polymer material.
13 . The expandable stent-graft of claim 12 , wherein the one or more fused portions are formed by melting the polymer material and/or by ultrasonic welding.
14 . The expandable stent-graft of claim 10 , wherein a channel length of the first internal flow channel and the second internal flow channel is between 50% and 90% of a hub length extending from a first rim of the first end to a second rim of the second end.
15 . The expandable stent-graft of claim 10 , wherein a channel length of the first internal flow channel and the second internal flow channel is between 75% and 90% of a hub length extending from a first rim of the first end to a second rim of the second end.
16 . The expandable stent-graft of claim 10 , wherein the first internal flow channel and the second internal flow channel are unsupported by the self-expanding wire stent.
17 . The expandable stent-graft of claim 10 , wherein the first cylindrical wall defines a first open end of the expandable stent-graft, and the second cylindrical wall defines a second open end of the expandable stent-graft.
18 . The expandable stent-graft of claim 10 , wherein the graft portion comprises a polymer material, and wherein the first cylindrical wall and the second cylindrical wall each include folded portions of the polymer material.
19 . The expandable stent-graft of claim 10 , wherein the graft portion comprises a single tube of polymer material and a total circumference of each of the main fluid flow channel, the first internal flow channel, and the second internal flow channel is equal to a circumference of the single tube of polymer material.