STRIPED SHEATHS FOR MEDICAL DEVICES

• US 20160317337A1
• Filed: 05/05/2016
• Published: 11/03/2016
• Est. Priority Date: 03/13/2014
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Duong, Khanh, McCoy, Jill A.
• Granted Patent: US 10,433,996 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/9524 Iris-type crimpers
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2/97 the outer sleeve being splittable
• CPC Class Codes: A61F 2002/9583 Means for holding the stent on the balloon, e.g. using protrusions, adhesives or an outer sleeve

Abstract

A sheath used to protect a medical device has one or more strips formed over a portion thereof. The medical device is a scaffold crimped to a balloon and mounted to a catheter. The sheath is two-piece, including a protecting and constraining sheath part. The strips facilitate removal of the constraining sheath from the scaffold in manner that reduces instances of damage caused by improper removal of the sheath from the medical device.

Claims

1. An apparatus, comprising:

a catheter having distal and proximal ends;

a scaffold crimped to a balloon at the catheter distal end; and

a two piece sheath assembly, including

a protecting sheath disposed over the scaffold,

a constraining sheath disposed over the protecting sheath, and

the constraining sheath including at least one strip;

wherein the crimped scaffold and balloon are configured for being placed within a body only after the two piece sheath assembly is pushed or pulled off the catheter distal end.

2. The apparatus of claim 1, wherein the protecting sheath includes two slots.

3. The apparatus of claim 2, wherein the two slots form separable halves.

4. The apparatus of claim 1, wherein the constraining sheath has a second and third portion each having lengths L2 and L3 and the scaffold has a length LS, wherein L2 and/or L3 is about equal to LS.

5. The apparatus of claim 4, wherein the sum L2+L3 is about twice LS.

6. The apparatus of claim 1, wherein the scaffold has a distal end and a proximal end, and

wherein a substantial portion of the at least one strip is disposed distally of the scaffold distal end and/or the catheter distal end.

7. The apparatus of claim 1, wherein more than 50% of a lengthwise extent of the at least one strip is located distally of the catheter distal end.

8. The apparatus of claim 1, wherein the constraining sheath comprises a plurality of slots, wherein the at least one strip is formed between a pair of slots.

9. The apparatus of claim 1, wherein the constraining sheath has a constraining portion devoid of a strip, and the constraining portion is disposed over the entire length of the scaffold.

10. The apparatus of claim 9, wherein the protecting sheath includes at least two slots, and the constraining portion is disposed over the two slots and the scaffold.

11. The apparatus of claim 1, wherein the at least one strip extends parallel to a longitudinal axis of the catheter.

12. The apparatus of claim 1, wherein the strip is a helical strip formed by a single helical slot having a helix angle.

13. The apparatus of claim 1, wherein a distal end of the constraining sheath comprises a portion of the at least one slot and strip.

14. The apparatus of claim 1, wherein the constraining sheath includes six slots and six strips, four slots and four strips, or two slots and two strips.

20. The apparatus of claim 1, the protecting sheath further comprising

a first and second end, each of the first and second ends having an outer diameter,

the constraining sheath has an outer diameter that is less than the outer diameters of each of the first and second ends, and

the constraining sheath is between the first and second ends.

15-17. -17. (canceled)

18. An apparatus, comprising:

a catheter including a scaffold crimped to a balloon; and

a sheath assembly including

a protecting sheath disposed over the scaffold,

a constraining sheath disposed over the protecting sheath,

the constraining sheath comprising a slot not disposed over the scaffold, and

the protecting sheath comprising a slot disposed over the scaffold.

19. The apparatus of claim 18, wherein the constraining sheath slot is located distally of a distal end of the scaffold and a constraining portion of the constraining sheath applies an inwardly directed radial pressure upon the scaffold to reduce recoil of the scaffold.

21. An apparatus, comprising:

a catheter including a scaffold crimped to a balloon; and

a sheath for the scaffold including a constraining sheath having a plurality of slots forming at least one strip not disposed over the scaffold;

wherein the strip deflects outwardly when the constraining sheath is removed from the scaffold;

wherein the scaffold undergoes plastic deformation when the balloon is inflated; and

wherein the scaffold recoils from a crimped state by no more than 10% when the sheath assembly is removed from the crimped scaffold and before the balloon is inflated.