Stent Prosthesis Having Select Flared Crowns

• US 20090248139A1
• Filed: 03/27/2008
• Published: 10/01/2009
• Est. Priority Date: 03/27/2008
• Status: Active Grant

• Current Assignee: Medtronic Vascular, Inc. (Medtronic Plc)
• Original Assignee: Medtronic Vascular, Inc. (Medtronic Plc)
• Inventors: Pellegrini, Gianfranco
• Granted Patent: US 8,034,099 B2
• Time in Patent Office: Days
• US Class Current: 623/1.170
• 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 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/821 Ostial stents
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

A generally tubular, cylindrical stent prosthesis has an unexpanded delivery configuration and an expanded configuration for contacting the vessel wall. The stent prosthesis has a plurality of adjacent stent struts, each stent strut having a wavelike or sinusoidal pattern of straight segments and crowns. A Y-shaped member is attached to one or more crowns to cause the crowns to flare outwardly at an angle from the cylindrical stent body when the stent is expanded. Upon expansion of the stent, the crown(s) having Y-shaped members attached thereto are angled with respect to the longitudinal axis and radially flare from the cylindrical stent body. The flared crowns anchor the stent within the vessel by protruding into the vessel wall and/or seating the stent within an ostium.

Claims

1. A stent for use within a body lumen, the stent comprising:

a stent strut having a sinusoidal pattern of straight segments and crowns, wherein all of the crowns of the stent strut are approximately parallel with a longitudinal axis of the stent when the stent is in an unexpanded configuration for delivery within the body lumen; and

a Y-shaped member attached to at least one crown of the stent strut such that the Y-shaped member is substantially centered within the at least one crown and the straight segments attached to the at least one crown,

wherein when the stent is in an expanded configuration for contacting a vessel wall of the body lumen the at least one crown having the Y-shaped member attached thereto radially flares outward from an outer surface of the stent such that the at least one crown is at an acute angle with respect to the longitudinal axis of the stent.

2. The stent of claim 1, wherein the at least one crown forms approximately a forty-five degree angle with respect to the longitudinal axis of the stent when the stent is in the expanded configuration.

3. The stent of claim 1, wherein the stent includes a plurality of stent struts formed into a plurality of radially expandable cylindrical rings aligned substantially parallel to the longitudinal axis so as to form a cylindrically-shaped tubular body.

4. The stent of claim 3, wherein the plurality of radially expandable cylindrical rings are aligned such that crowns of adjacent stent struts are aligned and at least one connection is formed between aligned crowns of adjacent stent struts.

5. The stent of claim 4, wherein the at least one crown is not connected to a crown of an adjacent stent strut.

6. The stent of claim 1, wherein the Y-shaped member includes a V-shaped base connected to the straight segments of the stent strut attached to the at least one crown and a tether extending from an apex of the V-shaped base to a valley formed by the at least one crown.

7. The stent of claim 6, wherein the Y-shape member approaches a T-shape when the stent is in the expanded configuration.

8. The stent of claim 7, wherein the tether applies longitudinal tension to the at least one crown such that the at least one crown lifts or projects outwardly from an outer surface of the stent when the stent is in the expanded configuration.

9. The stent of claim 1, wherein the at least one crown is an outermost crown located at a proximal end or a distal end of the stent.

10. The stent of claim 1, wherein the at least one crown is an interior crown located between a proximal end and a distal end of the stent.

11. The stent of claim 1, wherein the stent strut has a thickness that is constant along the length of the straight segment.

12. The stent of claim 1, wherein the stent strut has a thickness that varies along the length of the straight segment.

13. A method of implanting a stent within a body lumen, the method comprising the steps of:

tracking a balloon catheter having the stent loaded on a balloon of the balloon catheter to a target site within a body lumen, wherein the stent is in an unexpanded configuration sufficient for delivery within the body lumen and wherein the stent includes a stent strut having a sinusoidal pattern of straight segments and crowns facing opposite longitudinal directions and a Y-shaped member attached to at least one crown of the stent strut such that the Y-shaped member is substantially centered within the at least one crown and the straight segments attached to the at least one crown, all of the crowns of the stent strut being approximately parallel with a longitudinal axis of the stent when the stent is in the unexpanded configuration;

inflating the balloon of the balloon catheter;

radially expanding the stent to an expanded configuration contacting a vessel wall of the body lumen, wherein the at least one crown radially flares outward from an outer surface of the stent such that the at least one crown is angled with respect to the longitudinal axis of the stent when the stent is in the expanded configuration.

14. The method of claim 13, wherein the at least one crown forms approximately a forty-five degree angle with respect to the longitudinal axis of the stent when the stent is in the expanded configuration.

15. The method of claim 13, wherein the stent includes a plurality of stent struts formed into a plurality of radially expandable cylindrical rings aligned substantially parallel to the longitudinal axis so as to form a cylindrically-shaped tubular body and the plurality of radially expandable cylindrical rings are aligned such that crowns of adjacent stent struts are aligned and at least one connection is formed between the aligned crowns of adjacent stent struts.

16. The method of claim 13, wherein the Y-shaped member includes a V-shaped base connected to the straight segments of the stent strut attached to the at least one crown and a tether extending from an apex of the V-shaped base to a valley formed by the at least one crown and the tether applies longitudinal tension to the at least one crown such that the at least one crown lifts or projects outwardly from an outer surface of the stent when the stent is in the expanded configuration.

17. The method of claim 13, wherein the at least one crown is an outermost crown located at a proximal end or a distal end of the stent.

18. The method of claim 13, wherein the at least one crown is an interior crown located between a proximal end and a distal end of the stent.

19. The method of claim 13, wherein the stent strut has a thickness that is constant along the length of the straight segment.

20. The method of claim 13, wherein the stent strut has a thickness that varies along the length of the straight segment.