Growth adaptive expandable stent

Patent metadata

Field	Value
Publication number	US-2021353443-A1
Application number	US-201816637664-A
Country	US
Kind code	A1
Filing date	Aug 10, 2018
Priority date	Aug 11, 2017
Publication date	Nov 18, 2021
Grant date	—

Abstract

According to various aspects and embodiments, a growth adaptive expandable stent is provided. The expandable stent includes a stent structure having a cylindrical shape that is self-expanding in a radial direction and includes a plurality of cylindrical rings disposed along a longitudinal axis of the stent structure. The stent structure is configured to exert a continuous outward radial force over time when implanted such that a diameter of the stent structure expands from a first value to a second value that is at least about 1.5 times the first value.

First claim

What is claimed is:

1 . A growth adaptive expandable stent for use in a heart valve device, the expandable stent comprising:
a stent structure having a cylindrical shape that is self-expanding in a radial direction, the stent structure having a proximal end portion, a distal end portion, and a central portion and comprising a plurality of cylindrical rings disposed along a longitudinal axis of the stent structure, each cylindrical ring of the plurality of cylindrical rings having a plurality of interconnected struts; the stent structure configured to exert a chronic outward radial force over time when implanted such that an outer diameter of the stent structure expands from a first value to a second value that is at least about 1.5 times the first value.

2 . The growth adaptive expandable stent of claim 1 , wherein the chronic outward radial force is sufficient to allow the outer diameter of the stent structure to adapt to a natural growing shape of a biological feature in which the stent structure is implanted.

3 . The growth adaptive expandable stent of claim 1 , wherein the chronic outward radial force decreases by up to 100% when the outer diameter expands from the first value to the second value.

4 . The growth adaptive expandable stent of claim 1 , wherein the first value of the outer diameter is in a range of about 4 mm to about 20 mm.

5 . The growth adaptive expandable stent of claim 4 , wherein the first value of the outer diameter is in a range of about 5 mm to about 10 mm.

6 . The growth adaptive expandable stent of claim 1 , wherein, a ratio of a depth to a localized width of each strut allows for preferential bending.

7 . The growth adaptive expandable stent of claim 6 , wherein the stent structure is configured such that a length of the stent structure remains substantially constant when the outer diameter of the stent structure expands from the first value to the second value.

8 . The growth adaptive expandable stent of claim 6 , wherein the ratio of the depth of the strut to the localized width of the strut is greater than one.

9 . The growth adaptive expandable stent of claim 8 , wherein the depth of the strut is in a range of about 50 microns to about 2000 microns.

10 . The growth adaptive expandable stent of claim 6 , wherein the length of the stent structure is in a range of about 7 mm to about 30 mm when the outer diameter is the second value.

11 . The growth adaptive expandable stent of claim 1 , wherein the length of the stent structure is configured to prevent ingrowth of a patient's tissue into the stent structure without disrupting or occluding blood flow.

12 . The growth adaptive expandable stent of claim 11 , wherein a ratio of the length of the stent structure to the outer diameter of the stent structure is at least one.

13 . The growth adaptive expandable stent of claim 1 , further comprising a plurality of restraining structures disposed around the longitudinal axis of the stent structure.

14 . The growth adaptive expandable stent of claim 13 , wherein each restraining structure includes at least one retaining feature.

15 . The growth adaptive expandable stent of claim 14 , wherein at least one of the retaining features is a ring.

16 . The growth adaptive expandable stent of claim 14 , wherein at least one of the retaining features is a nubbin.

17 . The growth adaptive expandable stent of claim 13 , wherein each of the restraining structures is interspersed with the plurality of cylindrical rings.

18 . The growth adaptive expandable stent of claim 13 , wherein the plurality of restraining structures are interspersed with the plurality of cylindrical rings such that a pair of restraining structures are separated from one another by segments of the plurality of cylindrical rings.

19 . The growth adaptive expandable stent of claim 1 , wherein the plurality of interconnected struts are configured such that two adjacent struts are connected to each other at an apex.

20 . The growth adaptive expandable stent of claim 13 , wherein the stent structure and the plurality of restraining structures are formed from a common source material.

21 . The growth adaptive expandable stent of claim 20 , wherein the common source material is formed of a bio-compatible super-elastic material.

22 . The growth adaptive expandable stent of claim 1 , wherein the stent structure is configured to support a valve assembly.

23 . The growth adaptive expandable stent of claim 13 , wherein the stent structure is configured to support a valve assembly.

24 . The growth adaptive expandable stent of claim 23 , wherein the valve assembly has one or more leaflets and is secured to at least one of the stent structure and the plurality of restraining structures.

25 . The growth adaptive expandable stent of claim 13 , wherein the stent structure and the plurality of restraining structures are configured for a pediatric patient.

26 . The growth adaptive expandable stent of claim 13 , further comprising a sheath disposed on outer surfaces of the stent structure.

27 . The growth adaptive expandable stent of claim 1 , further comprising a sheath disposed on outer surfaces of the stent structure.

28 . The growth adaptive expandable stent of claim 1 , further comprising
an annular cuff secured to at least a portion of the central portion of the stent structure.

29 . The growth adaptive expandable stent of claim 1 , wherein the outer diameter of the stent structure expands from the first value to the second value, and the second value is between about 1.5 times the first value and about 5 times the first value.

30 . The growth adaptive expandable stent of claim 29 , wherein the outer diameter of the stent structure expands from the first value to the second value, and the second value is between about 1.5 times the first value and about 3 times the first value.

31 . The growth adaptive expandable stent of claim 1 , wherein the outer diameter of the stent structure expands from the first value to the second value, and the second value is at least twice the first value.

32 . The growth adaptive expandable stent of claim 31 , further comprising a plurality of restraining structures disposed around a circumferential axis of the stent structure and interspersed with the plurality of cylindrical rings of the stent structure.

33 . The growth adaptive expandable stent structure of claim 32 , further comprising an annular cuff secured to at least a portion of the central portion of the stent structure.

34 . The growth adaptive expandable stent of claim 33 , further comprising a sheath disposed on outer surfaces of the stent structure.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• King Daniel F
• Golmon Stephanie Lynne
• Coppeta Jonathan R
• Carr Jesse M
• Williams Corin

Classifications

• A61F2/89 Primary

  the wire-like elements comprising two or more adjacent rings flexibly connected by separate members · CPC title

• A61F2210/0014

  using shape memory or superelastic materials, e.g. nitinol · CPC title

• A61F2250/0082

  specially designed for children, e.g. having means for adjusting to their growth · CPC title

• A61F2/2418 Primary

  Scaffolds therefor, e.g. support stents · CPC title

• A61F2220/0075

  sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable · CPC title