Noncylindrical stent deployment system for treating vascular bifurcations

• US 20050096726A1
• Filed: 10/29/2004
• Published: 05/05/2005
• Est. Priority Date: 05/30/2000
• Status: Active Grant

• Current Assignee: Biosensors International Group, Ltd.
• Original Assignee: Biosensors International Group, Ltd.
• Inventors: Elicker, Robert John, Laborde, Jean-Claude, Sequin, Jacques
• Granted Patent: US 8,236,041 B2
• Time in Patent Office: Days
• US Class Current: 623/1.12
• CPC Class Codes: A61F 2/856 Single tubular stent with a side portal passage
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2/9517 handle assemblies therefor
• CPC Class Codes: A61F 2/954 for placing stents or stent-grafts in a bifurcation
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61F 2/9661 the proximal portion of the stent or stent-graft is released first
• CPC Class Codes: A61F 2002/067 modular
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/9583 Means for holding the stent on the balloon, e.g. using protrusions, adhesives or an outer sleeve
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded

Abstract

A device and method for treating pathological narrowing of fluid-carrying conduits of the human body (such as blood vessels) in an area of a bifurcation is disclosed. In particular, a stent system carries a self expandable noncylindrical stent, which is particularly suited for treating a widened portion of a blood vessel immediately proximal to a bifurcation. A stent delivery system is also disclosed, for delivering the stent such that a larger expanded diameter end of the stent faces the bifurcation, and a smaller expanded diameter end of the stent faces proximally in the main vessel.

Claims

1. A deployment system for treating a bifurcation of a main vessel and a first and second branch vessels, comprising:

an elongate, flexible body, having a proximal end and a distal end;

a first stent carried by the distal end of the body; and

a releasable restraint, for retaining the stent on the flexible body;

wherein the distal end of the stent is larger in diameter than the proximal end of the stent in an unconstrained expanded configuration.

2. A deployment system as in claim 1, further comprising a guidewire lumen extending axially through at least a portion of the flexible body.

3. A deployment system as in claim 2, wherein the guidewire lumen has a proximal access port and a distal access port, and the proximal access port is positioned along the flexible body, spaced distally apart from the proximal end.

4. A deployment system as in claim 2, wherein the guidewire lumen has a proximal access port and a distal access port, and the proximal access port is positioned at the proximal end of the flexible body.

5. A deployment system as in claim 1, wherein the releasable restraint comprises an axially movable control element extending along the length of the flexible body.

6. A deployment system as in claim 1, wherein the releasable restraint comprises a tubular sheath.

7. A deployment system as in claim 1, wherein the releasable restraint comprises a pull wire.

8. A deployment system as in claim 1, wherein the releasable restraint comprises a dissolvable media.

9. A deployment system as in claim 1, further comprising a second stent carried by the distal end of the body.

10. A deployment system as in claim 9, wherein the first and second stents have different expanded geometries from each other.

11. A deployment system as in claim 10, wherein the second stent has a substantially cylindrical unconstrained expanded configuration, having a proximal end, a distal end and a substantially constant radius throughout.

12. A deployment system as in claim 1, wherein the expanded diameter of the first stent tapers radially outwardly in the distal direction.

13. A deployment system as in claim 9, wherein the first and second stents are carried by the catheter such that release of the stents from the catheter causes the distal end of the first stent and the proximal end of the second stent, as implanted, to be separated by a distance of no more than about 4 mm.

14. A deployment system as in claim 13, wherein the distance is no more than about 2 mm.

15. A method of treating a vascular bifurcation of a main vessel into first and second branch vessels, comprising the steps of:

deploying a substantially cylindrical stent in a first branch vessel which is distal to the bifurcation; and

deploying a tapered stent in the main vessel, proximal to the bifurcation;

wherein the tapered stent tapers in the distal direction from a smaller proximal diameter to a larger distal diameter which faces the bifurcation.

16. A method of treating a vascular bifurcation as in claim 15, wherein at least one of the substantially cylindrical stent and the tapered stent is deployed from a delivery catheter by proximally retracting an outer sheath on the delivery catheter.

17. A stent deployment catheter, comprising:

an elongate, flexible tubular body, having a proximal end and a distal end;

a noncylindrical, self expandable stent carried by the distal end;

a handpiece on the proximal end;

a control on the handpiece, having a first position for indicating partial deployment of the stent, and a second position indicating complete deployment of the stent.

18. A stent deployment catheter as in claim 17, further comprising a guidewire lumen, in an over the wire configuration.

19. A stent deployment catheter as in claim 17, further comprising a guidewire lumen, in a rapid exchange configuration.