HYDROGEL JACKETED STENTS

• US 20120089218A1
• Filed: 10/10/2011
• Published: 04/12/2012
• Est. Priority Date: 10/11/2010
• Status: Active Grant

• Current Assignee: Peter S. Dardi
• Original Assignee: Peter S. Dardi
• Inventors: Dardi, Peter S.
• Granted Patent: US 9,572,653 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• 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 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• 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 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0057 stretchable
• CPC Class Codes: A61F 2210/0061 swellable
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2250/0003 having an inflatable pocket filled with fluid, e.g. liquid or gas
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61F 2250/0069 Sealing means
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

Hydrogel jacketed stents provide the ability to fill in the stent frame in vivo to at least partially cover the interior of the surface of the stent following deployment while having the convenience of attaching the jacket to the exterior of the stent. The hydrogel can be pleated and/or folder over the exterior of the stent to provide for extension of the stent without damaging the hydrogel. The hydrogel sheet can be secured at one or more points along the circumference to associate the sheet of hydrogel with the exterior surface of the stent frame. The stent can be conveniently delivered using similar technology as conventional stents if desired. The hydrogel can provide for drug delivery if desired.

Claims

1. A jacketed stent for placement in a bodily vessel comprising an extendable stent frame having an exterior surface defined by the stent frame and a hydrogel sheet associated with the exterior surface of the scaffold such that the hydrogel forms a jacket over the stent frame upon extension of the stent frame to its extended configuration, wherein the hydrogel sheet has a thickness and expansion in an aqueous fluid such that the expanded hydrogel sheet at least partially covers the inner surface of the extended stent in an aqueous environment.

2. The jacketed stent of claim 1 wherein the ratio of the extended diameter of the stent frame to the un-extended diameter of the stent frame is from about 2 to about 6.

3. The jacketed stent of claim 1 wherein the stent frame is open.

4. The jacketed stent of claim 1 wherein the stent frame comprises a metal.

5. The jacketed stent of claim 1 wherein the hydrogel swells by a factor of at least about 1.5 in thickness relative to its initial thickness upon exposure to an aqueous environment.

6. The jacketed stent of claim 1 wherein hydrogel sheet has a thickness from about 0.001 nun to about 0.5 mm.

7. The jacketed stent of claim 1 wherein hydrogel sheet covers the outer surface of the stent frame except for a portion at the ends of the stent frame.

8. The jacketed stent of claim 1 wherein hydrogel sheet does not cover a portion of the stent frame and the jacketed stent further comprising radiopaque markers indicating the uncovered portion of the stent.

9. A medical device comprising a delivery catheter, a delivery actuator supported by the delivery catheter and a jacketed stent of claim 1 operably connected with the delivery actuator to control deployment of the stent in a vessel.

10. The medical device of claim 9 wherein the delivery actuator comprises a sheath that slides relative to the delivery catheter and wherein the delivery sheath has a configuration in which the stent is constrained between the deliver catheter and the sheath and a configuration in which the stent is unconstrained, and wherein the stent is self expanding.

11. The medical device of claim 9 wherein the delivery actuator comprises a balloon that is positioned on the deliver catheter such that the expansion on the balloon expands the stent, and wherein the delivery catheter further comprises a balloon flow channel operably connected to a fluid reservoir such that fluid from the reservoir can be transported in a controlled way to expand the balloon.

12. A jacketed stent comprising a stent frame having an outer surface and a hydrogel sheet associated with the outer surface of the stent frame, wherein the hydrogel sheet is folded to accommodate a larger surface area of the hydrogel sheet relative to the outer surface of the stent frame and wherein the stent frame extends to a deployed configuration with the hydrogel sheet stretched along the outer surface of the stent frame.

13. The jacketed stent of claim 12 wherein the hydrogel sheet is pleated.

14. The jacketed stent of claim 12 wherein the hydrogel sheet is wrapped around the stent frame.

15. The jacketed stent of claim 12 wherein the hydrogel sheet is secured along a point on the circumference of the stent frame.

16. The jacketed stent of claim 12 wherein the hydrogel sheet is secured along a plurality of points on the circumference of the stent frame.

17. A jacketed stent comprising:

a stent frame having an open structure, an outer surface, and a extended configuration with a diameter at least about a factor of two greater than its initial configuration; and

a hydrogel sheet associated with the outer surface of the stent frame, wherein the hydrogel sheet hydrates to an expanded form with a thickness at least about 1.5 greater than its initial thickness.

18. A method of forming a hydrogel jacketed stent, the method comprising securing a hydrogel sheet over an extendable stent frame in a low profile configuration, wherein the hydrogel is structured to provide for expansion in diameter by at least of the stent frame by a factor of at least about 2 and wherein the hydrogel expands upon hydration to a thickness at least about 1.5 times the initial thickness of the sheet.

19. The method of claim 18 wherein hydrogel jacket is folded and/or pleated around the stent frame such that the hydrogel jacket unfolds when the stent scaffolding deployed to an extended configuration with a greater diameter.

20. A method for the delivery of a hydrogel jacketed stent comprising extending the stent to an extended configuration within the lumen of a vessel within a patient, wherein the stent comprises an open structured stent frame having an outer surface and a hydrogel jacket associated with the outer surface, wherein the extended stent has the hydrogel jacket secured between the vessel wall and the stent frame such that the hydrogel hydrates and expands to fill the open portions of the stent frame after sufficient time to provide for hydration of the hydrogel.