Systems and methods for delivery of stents and stent-like devices
Systems for completely or partially excluding an aneurysm from circulation of blood are described. In one embodiment, the system includes a microcatheter, a fully or partially self-expandable stent, and a delivery device configured to be deliverable together with the stent through a lumen of the microcatheter. The delivery device includes an elongate support member coupled to a self-expandable portion, which includes a tubular mesh structure having a compressed state and an expanded state. A distal portion of the self-expandable portion extends proximally from a distal end of the self-expandable portion and has a length having an expanded outer diameter that is equal to or greater than the self-expanded inner diameter of the stent. In some embodiments, the proximal end of the self-expandable portion is substantially non-expanded where it is coupled to the elongate support member.
1. A system for treating an aneurysm, comprising:
a microcatheter comprising a proximal end, a distal end, and a lumen therebetween,
a fully or partially self-expandable stent having a first end and a second end deliverable through the lumen of the microcatheter, the stent having a self-expanded inner diameter; and
a delivery device deliverable together with the stent through the lumen of the microcatheter, the delivery device comprising an elongate support member having a proximal end and a distal end and a self-expandable portion having a proximal end, a distal end, an outer surface, and an inner surface, the proximal end of the self-expandable portion coupled at or near the distal end of the elongate support member;
wherein the self-expandable portion of the delivery device comprises a tubular mesh structure having a compressed state and an expanded state, wherein the self-expandable portion has an open distal end, wherein a distal portion of the self-expandable portion extending proximally from the distal end of the self-expandable portion has a length having an expanded outer diameter, and the proximal end of the self-expandable portion is substantially non-expanded where it is coupled to the elongate support member;
wherein the expanded outer diameter of the distal portion of the self-expandable portion is equal to or greater than the self-expanded inner diameter of the stent, and
wherein in a configuration in the lumen of the microcatheter, the fully or partially self-expandable stent is engaged with the outer surface of the self-expandable portion of the delivery device along a length of the self-expandable stent from the first end to the second end,
wherein in a delivery configuration,
at least a portion of the delivery device is positioned distal to the distal end of the microcatheter,
at least a portion of the fully or partially self-expandable stent is positioned distal to the distal end of the microcatheter, and
the fully or partially self-expandable stent is engaged with the outer surface of the self-expandable portion of the delivery device.
2. The system of claim 1 , wherein the self-expanded inner diameter of the stent tapers in diameter over a taper length positioned between the first end and the second end of the stent.
3. The system of claim 1 , wherein the expanded outer diameter of the distal portion of the self-expandable portion of the delivery device tapers in diameter.
4. The system of claim 1 , wherein the stent comprises a tubular mesh.
5. The system of claim 1 , wherein the stent comprises a slotted tube having a plurality of struts.
6. The system of claim 1 , wherein mechanical engagement between the expanded outer diameter of the distal portion of the self-expandable portion of the delivery device and the self-expanded inner diameter of the stent maintains the stent on the self-expandable portion.
7. The system of claim 6 , wherein the mechanical engagement between the expanded outer diameter of the distal portion of the self-expandable portion of the delivery device and the self-expanded inner diameter of the stent maintains the stent on the self-expandable portion with an axial separation force of at least 227 grams.
8. The system of claim 7 , wherein the mechanical engagement between the expanded outer diameter of the distal portion of the self-expandable portion of the delivery device and the self-expanded inner diameter of the stent maintains the stent on the self-expandable portion with an axial separation force of at least 454 grams.
9. The system of claim 6 , wherein the mechanical engagement is predominantly due to frictional engagement.
10. The system of claim 6 , wherein the mechanical engagement is predominantly due to intermeshing.
11. The system of claim 1 , wherein in the delivery configuration, the fully or partially self-expandable stent is positioned entirely distal to the distal end of the microcatheter.
12. The system of claim 1 , wherein in the delivery configuration, the self-expandable portion of the delivery device is positioned entirely distal to the distal end of the microcatheter.