ENDOLUMINAL PROSTHETIC ASSEMBLIES, AND ASSOCIATED SYSTEMS AND METHODS FOR PERCUTANEOUS REPAIR OF A VASCULAR TISSUE DEFECT

• US 20170224467A1
• Filed: 02/09/2016
• Published: 08/10/2017
• Est. Priority Date: 02/09/2016
• Status: Active Grant

• Current Assignee: Medtronic Vascular, Inc. (Medtronic Plc)
• Original Assignee: Medtronic Vascular, Inc. (Medtronic Plc)
• Inventors: Coghlan, Kieran, Galligan, Darren, Piccagli, Francesco, Guala, Carlo, Morero, Massimo, Argentine, Jeffery
• Granted Patent: US 10,070,950 B2
• Time in Patent Office: Days
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/852 Two or more distinct overlapping stents
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• 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 2002/061 provided with means for allowing access to secondary lumens
• CPC Class Codes: A61F 2002/067 modular
• CPC Class Codes: A61F 2002/077 having means to fill the space between stent-graft and aneurysm wall, e.g. a sleeve
• CPC Class Codes: A61F 2002/826 more than one stent being applied sequentially
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0061 swellable
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/0008 elliptical or oval
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2250/0003 having an inflatable pocket filled with fluid, e.g. liquid or gas
• CPC Class Codes: A61F 2250/0004 adjustable
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: A61F 2250/006 modular
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• CPC Class Codes: A61F 2250/0069 : Sealing means
• CPC Class Codes: A61F 2250/0096 : Markers and sensors for detecting a position or changes of a position of an implant, e.g. RF sensors, ultrasound markers

Abstract

A prosthetic assembly for repairing a target tissue defect within a target vessel region configured includes an exclusion structure sized to substantially bypass target tissue defect, and includes a branch assembly. The branch assembly can include a self-expanding outer branch prosthesis having an inflow region configured to deform to a non-circular cross-sectional-shape when deployed, and a support structure at least partially disposed within the inflow region. The support structure preserves blood flow to the branch vessel while the deformed inflow region inhibits blood leakage between and/or around the prosthetic assembly.

Claims

1. :

A prosthetic assembly for repairing a target tissue defect within a target vessel region in a patient, the prosthetic assembly comprising;

an exclusion structure sized to substantially cover the target tissue defect in the target vessel region when the exclusion structure is in a deployed configuration; and

a branch assembly for directing fluid flow to a branch vessel from the target vessel region, the branch assembly comprising,

an outer branch prosthesis having a first portion and a second portion, wherein the first portion is configured to be deployed between the exclusion structure and a wall of the target vessel region, and the second portion is configured to be deployed in a branch vessel branching from the target vessel region, and

a support structure at least partially disposed within the outer branch prosthesis at the first portion when the branch assembly is in a deployed configuration,

wherein an inflow region of the first portion of the outer branch prosthesis is expandable to a cross-sectional dimension larger than a cross-sectional dimension of the support structure, and wherein the first portion is deformable to a non-circular cross-sectional shape when deployed.

2. :

The prosthetic assembly of claim 1, wherein the inflow region is configured to deform to the non-circular cross-sectional shape to conform to the wall of the target vessel region and an outer surface of the exclusion structure.

3. :

The prosthetic assembly of claim 1, wherein the cross-sectional shape of the support structure remains sufficiently stable when the inflow region of the outer branch prosthesis is deformed to the non-circular cross-sectional shape.

4. :

The prosthetic assembly of claim 3, wherein the support structure is substantially circular in cross-section to maintain patency of the first portion of the outer branch prosthesis.

5. :

The prosthetic assembly of claim 1, wherein the outer branch prosthesis includes a frame and graft material coupled to the frame, wherein at least a portion of the frame at the first portion of the outer branch prosthesis comprises two or more posts oriented lengthwise along the first portion, and wherein the posts provide a deformation orientation plane such that when deformed, the cross-sectional shape is substantially elliptical.

6. :

The prosthetic assembly of claim 1, wherein the inflow region is configured to be deformable to an oval cross-sectional shape by the exclusion structure when the prosthetic assembly is deployed at the target vessel region.

7. :

The prosthetic assembly of claim 1, wherein the inflow region has a first cross-sectional dimension and the second portion has a second cross-sectional dimension less than the first cross-sectional dimension.

8. :

The prosthetic assembly of claim 1, wherein the support structure has a central longitudinal axis and a first radial strength oriented in an outward, radial direction from the longitudinal axis, and wherein the outer branch prosthesis has a second radial strength oriented in an outward, radial direction from the central longitudinal axis, and wherein the second radial strength is less than the first radial strength.

9. :

The prosthetic assembly of claim 1, wherein the first portion of the outer branch prosthesis has a central longitudinal axis, and wherein the support structure is configured to be deployed coaxially with the first portion of the branch stent along the central longitudinal axis.

10. :

The prosthetic assembly of claim 1, wherein the support structure is a balloon-expandable stent.

11. :

The prosthetic assembly of claim 1, wherein the support structure is a self-expanding stent.

12. :

The prosthetic assembly of claim 1, wherein the exclusion structure is an endoprosthetic stent-graft and a proximal portion of the branch assembly is configured to be deployed in parallel with a proximal portion of the endoprosthetic stent-graft.

13. :

The prosthetic assembly of claim 12, wherein the target tissue defect is an abdominal aortic aneurism, and wherein the endoprosthetic stent-graft is configured to be implanted in the aorta in a manner to bypass the aneurism.

14. :

The prosthetic assembly of claim 1, further comprising a second branch assembly for directing fluid flow to a second branch vessel from the target vessel region.

15. :

The prosthetic assembly of claim 1, wherein the support structure includes an upstream end and a downstream end, and wherein the upstream end extends a distance in an upstream direction beyond a proximal end of the first portion of the outer branch prosthesis.

16. :

The prosthetic assembly of claim 1, wherein the inflow region of the outer branch prosthesis includes a rim at a proximal end of the inflow region, the rim having an undeformed configuration, the undeformed configuration having a generally circular shape.

17. :

The prosthetic assembly of claim 1, wherein the support structure has a longitudinal axis, and wherein the inflow region of the outer branch assembly in a radially expanded, unconstrained configuration flares outward from the longitudinal axis by a taper angle.

18. :

The prosthetic assembly of claim 17, wherein the taper angle continuously changes between a transition point of the inflow region and a rim at a proximal end of the inflow region.

19. :

The prosthetic assembly of claim 1, wherein;

the first portion of the outer branch prosthesis includes a plurality of first struts interconnected around a circumference of the first portion;

the support structure includes a plurality of second struts interconnected around a circumference of the support structure; and

the second struts are more rigid than the first struts.

20. :

The prosthetic assembly of claim 1, wherein the first portion of the outer branch prosthesis has a frustoconical shape in a radially expanded, unconstrained configuration.

21. :

The prosthetic assembly of claim 1, wherein the exclusion structure is configured to provide a compressive force against the branch assembly, and wherein the compressive force is sufficient to deform the outer branch prosthesis without substantially deforming the support structure deployed within the outer branch prosthesis.

22. :

A system to treat a blood vessel defect in a patient, the system comprising;

a prosthetic stent-graft device having an exclusion structure for bypassing the blood vessel defect in a main blood vessel;

a branch assembly configured to direct blood flow into one or more branch blood vessels from the main blood vessel while inhibiting leakage of blood into the target tissue defect, the branch assembly comprising,

an outer branch stent-graft configured to self-expand to form a blood flow path from proximal of the prosthetic stent-graft device in the main blood vessel to the branch blood vessel when the branch assembly is in a deployed configuration, the outer branch stent-graft having an inflow region with a first cross-sectional dimension at a first portion and a second portion with a second cross-sectional dimension less than the first cross-sectional dimension, and

an inner support structure at least partially disposed within the first portion of the outer branch stent-graft, wherein the inner support structure has a third cross-sectional dimension less than the first cross-sectional dimension,

wherein the first portion of the outer branch stent-graft has a first outward-oriented radial strength and the inner support structure has a second outward-oriented radial strength greater than the first outward-oriented radial strength; and

a delivery catheter having a lumen configured to retain at least the branch assembly in a delivery configuration, the delivery configuration having a lower profile than the deployed configuration.

23. :

The system of claim 22, wherein the delivery catheter comprises a retractable sheath and the branch assembly is contained within the sheath in the delivery configuration, and wherein at least the outer branch stent-graft is configured to resiliently expand when the sheath is retracted.

24. :

The system of claim 22, wherein the delivery catheter further comprises a balloon assembly for transitioning the inner support structure from the delivery configuration to the deployed configuration.

25. :

The system of claim 22, wherein the delivery catheter is configured to simultaneously deliver and sequentially deploy the outer branch stent-graft and the inner support structure in a vicinity of the blood vessel defect in the patient.

26. :

The system of claim 22, wherein the exclusion structure in the deployed configuration provides a compressive force against the branch assembly, and wherein the compressive force is sufficient to deform the outer branch stent-graft without substantially deforming the inner support structure deployed within the outer branch stent-graft.

27. :

The system of claim 22, wherein;

the inner support structure is at least partially surrounded by the inflow region of the outer branch stent-graft, and the inner support structure is configured to maintain patency of the branch assembly at a proximal region of the branch assembly; and

the inflow region of the outer branch stent-graft is deformable to a non-circular cross-section while the inner support structure remains substantially circular in cross-section.

28. :

A method for repairing a target tissue defect in a blood vessel of a patient, the method comprising;

positioning a branch assembly in a radially-contracted configuration within a region of the blood vessel having the target tissue defect, wherein a distal segment of the branch assembly is disposed within a branch vessel and a proximal segment of the branch assembly is disposed within the blood vessel, and wherein the branch assembly includes,

an outer branch stent-graft having an inflow region at the proximal segment; and

an inner support structure configured to be at least partially disposed within the inflow region at the proximal segment of the branch assembly;

positioning an exclusion structure in the blood vessel, wherein at least a proximal portion of the exclusion structure is adjacent to the proximal segment of the branch assembly in the blood vessel, and wherein a central portion of the exclusion structure is aligned with the target tissue defect in the blood vessel;

expanding the exclusion structure in the blood vessel such that the central portion bypasses the target tissue defect in the blood vessel,

expanding the branch assembly to a deployed configuration, wherein the proximal portion of the exclusion structure at least partially deforms the inflow region of the outer branch stent-graft without substantially deforming the inner support structure.

29. :

The method of claim 28, wherein expanding the branch assembly comprises;

retracting a delivery sheath from the branch stent assembly to release the outer branch stent-graft to self-expand into a space between the exclusion structure and a wall of the blood vessel, wherein the outer branch stent-graft includes a sealing material for providing a barrier to blood flow between the wall and the exclusion structure.

30. :

The method of claim 29, wherein

after retracting the delivery sheath to release the outer branch stent-graft to self-expand, expanding the branch assembly further comprises expanding the inner support structure with a balloon assembly.

31. :

The method of claim 29, wherein after retracting the delivery sheath to release the outer branch stent-graft to self expand, expanding the branch stent assembly further comprises further retracting the delivery sheath from the inner support structure and allowing the inner support structure to self-expand to a preformed position and shape.

32. :

The method of claim 28, wherein the step of positioning the branch assembly comprises

delivering the branch assembly by a first catheter to the region prior to positioning the exclusion structure in the blood vessel, and wherein the branch assembly is positioned at the region in the delivery catheter.

33. :

The method of claim 28, wherein the outer branch stent-graft and the support structure are both disposed in a first delivery catheter prior to deployment, wherein expanding the branch assembly to a deployed configuration further includes;

deploying the outer branch stent-graft from the first delivery catheter,

after deploying the outer branch stent-graft, advancing the first delivery catheter such that the support structure is at least partially disposed within the outer branch stent-graft, and

after advancing the first delivery catheter, deploying the support structure at least partially within the outer branch stent-graft.

34. :

The method of claim 33, wherein the first delivery catheter includes an inner member coupled to a distal tip, further comprising after deploying the outer branch stent-graft and before advancing the first delivery catheter, retracting the inner member and the distal tip such that when the first delivery catheter is advanced, the distal tip does not extend too far into the branch vessel.