Prosthesis and deployment catheter for treating vascular bifurcations
A stepped balloon catheter prosthesis deployment system is disclosed for placement of a prosthesis across an Os opening from a main body lumen to a branch body lumen. The prosthesis comprises a radially expansible support at one end, a circumferentially extending link at the other end and at least one frond extending axially therebetween. The prosthesis is configured to be deployed from a stepped diameter balloon with the support in the branch body lumen, with the circumferentially extending link in the main lumen and the frond extendable across the Os.
1. A prosthesis and deployment catheter system for treating an opening from a main body lumen to a branch body lumen, the prosthesis comprising:
a radially expansible support, the support configured to be deployed in at least a portion of the branch body lumen;
a plurality of fronds extending axially from circumferentially spaced locations on an end of the radially expansible support, the fronds being configured to be positioned across the opening and into the main body lumen, each frond having a first section with four side-by-side filaments and a second section having two side-by-side filaments; and
at least one circumferential link connected to the plurality of fronds at circumferentially spaced locations, the circumferential link spaced axially apart from the support, wherein each frond is connected with the circumferential link at a single location, and
wherein the prosthesis is mounted on a balloon catheter such that the radially expansible support is carried by a first portion of a balloon that extends longitudinally along a longitudinal axis of the balloon, the first portion being inflatable to a first diameter and the circumferential link is carried by a second portion of a balloon that extends longitudinally along the longitudinal axis of the balloon, the second portion being inflatable to a second diameter that is larger than the first diameter.
2. The system of claim 1 , wherein the circumferential link connects each of the plurality of fronds.
3. The system of claim 1 , wherein the plurality of fronds includes at least three fronds.
4. The system of claim 1 , wherein the balloon catheter comprises a single, stepped balloon having a proximal section with a larger inflated diameter than an inflated diameter of a distal section.
5. The system as in claim 4 , wherein at least a portion of the radially expansible support comprises a drug coating, and at least a portion of the fronds and the circumferential link are without a drug coating.
6. The system of claim 5 , wherein the drug coating is configured to produce at least one of a controlled drug release rate, a constant drug release rate, bi-modal drug release rate or a controlled concentration of drug proximate a target vessel wall.
7. The system of claim 5 , wherein the drug coating comprises one or more of an anti-cell proliferative, anti-cell migration, anti-neo-plastic, or anti-inflammatory drug.
8. The system of claim 5 , wherein the drug coating is configured to reduce an incidence or amount of restenosis.
9. The system of claim 5 , wherein the drug coating includes a first drug and second a drug.
10. The system of claim 5 , wherein the drug coating includes a first coating and a second coating.
11. The system of claim 10 , wherein the first coating is configured to produce a first drug release rate and the second coating is configured to produce a second drug release rate.
12. The system of claim 4 , wherein the single, stepped balloon has an inflated stepped configuration at a relatively low inflation pressure.
13. The system of claim 12 , wherein the relatively low inflation pressure is less than or equal to about 5 atmospheres.
14. The system of claim 13 , wherein the relatively low inflation pressure is about 1 atmosphere.
15. The system of claim 1 , wherein the first portion and the second portion of the balloon comprise portions of the same balloon.
16. The system of claim 1 , wherein the circumferential link is configured to be deployed in at least a portion of the main body lumen and to apply less radial force to adjacent tissue than the expanded support applies in the branch body lumen.
17. A prosthesis and deployment catheter system for treating an opening from a main body lumen to a branch body lumen, the prosthesis comprising:
a balloon catheter comprising an elongate body having a proximal end, a distal portion, a first balloon portion extending along a first axis and coupled with a distal portion of the elongate body, and a second balloon portion extending along a second axis and coupled with the distal portion of the elongate body proximal of the first balloon portion, the first and second balloon portions being coaxial, the first balloon portion being inflatable to a first diameter and the second balloon portion being inflatable to a second diameter that is greater than the first balloon portion;
a radially expansible support, the support configured to be deployed in at least a portion of the branch body lumen, the support having a first wall pattern configured to provide scaffolding for a branch vessel;
a plurality of fronds extending axially from circumferentially spaced locations on an end of the support, the fronds comprising a transition zone having a second wall pattern different from the first wall pattern, the second wall pattern configured to provide scaffolding for an ostium between a branch vessel and a main vessel, the fronds further comprising a proximal portion located proximal of the transition zone, the proximal portion of the fronds having a third wall pattern different from the first and second wall patterns;
at least one circumferential link connected to the plurality of fronds at circumferentially spaced locations of the circumferential link, the circumferential link spaced axially apart from the support, wherein each frond is coupled with the circumferential link at a single location, and
wherein the prosthesis is mounted on the balloon catheter such that the radially expansible support is carried by the first balloon portion and the circumferential link is carried by the second balloon portion.
18. The prosthesis and deployment catheter system of claim 17 , wherein the balloon catheter comprises a single balloon having an inflated stepped configuration at a relatively low inflation pressure.
19. The system of claim 18 , wherein the relatively low inflation pressure is about 1 atmosphere.
20. The system of claim 17 , wherein the circumferential link is configured to be deployed in at least a portion of the main body lumen and to apply less radial force to adjacent tissue than the expanded support applies in the branch body lumen.