Welded stent having a welded soluble core

• US 9,675,477 B2
• Filed: 02/19/2016
• Issued: 06/13/2017
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Medtronic Vascular, Inc. (Medtronic Plc)
• Original Assignee: Medtronic Vascular, Inc. (Medtronic Plc)
• Inventors: Thompson, Dustin
• Primary Examiner(s): Saad, Erin
• Assistant Examiner(s): GAMINO, CARLOS J
• Application Number:
  US15/047,675
• Publication Number:
  US 20160167175A1
• Time in Patent Office: 480 Days
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of 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 2002/825 having longitudinal struts
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0031 made from both resorbable and non-resorbable prosthetic parts, e.g. adjacent parts
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: B23K 11/11 Spot welding
• CPC Class Codes: B23K 26/22 Spot welding
• CPC Class Codes: B23K 31/02 relating to soldering or welding dip or wave soldering in the manufacture of printed circuits H05K3/34
• CPC Class Codes: B23K 9/007 Spot arc welding

Abstract

A welded stent and stent delivery system, with a stent including a first strut having a first strut nickel titanium alloy layer and nickel titanium soluble core, the first strut nickel titanium alloy layer being disposed around the first strut nickel titanium soluble core; and a second strut having a second strut nickel titanium alloy layer and nickel titanium soluble core, the second strut nickel titanium alloy layer being disposed around the second strut nickel titanium soluble core, the second strut nickel titanium alloy layer being connected to the first strut nickel titanium alloy layer with a weld. The first and second strut nickel titanium alloy layers are made of a nickel titanium alloy, the first and second strut nickel titanium soluble cores are made of a nickel titanium soluble material, and the weld is made of an alloy of the nickel titanium alloy and the nickel titanium soluble material.

Claims

1. A method of manufacturing a stent comprising:

providing a first strut having in transverse cross section a first strut nickel titanium alloy layer and a first strut soluble core, the first strut nickel titanium alloy layer being disposed around and immediately adjacent to the first strut soluble core, the first strut nickel titanium alloy layer being made of a nickel titanium alloy, the first strut soluble core being made of a soluble material;

providing a second strut having in transverse cross section a second strut nickel titanium alloy layer and a second strut soluble core, the second strut nickel titanium alloy layer being disposed around and immediately adjacent to the second strut soluble core, the second strut nickel titanium alloy layer being made of the nickel titanium alloy, the second strut soluble core being made of the soluble material;

positioning the first strut adjacent to the second strut at a weld point;

at the weld point, melting portions of the first strut nickel titanium alloy layer, the first strut soluble core, the second strut nickel titanium alloy layer, and the second strut soluble core;

at the weld point, mixing the melted portions of the first strut nickel titanium alloy layer, the second strut nickel titanium alloy layer, the first soluble core, and the second soluble core to form a weld pool; and

cooling the weld pool to form a weld connecting together the first strut nickel titanium alloy layer, the second strut nickel titanium alloy layer, the first soluble core, and the second soluble core;

wherein the soluble material is selected from the group consisting of chromium, molybdenum, mixtures thereof, and alloys thereof.

2. The method of claim 1 wherein the weld further connects the first strut soluble core and the second strut soluble core.

3. The method of claim 1 further comprising removing the first strut soluble core to form a first strut central void.

4. The method of claim 3 further comprising filling the first strut central void with a drug.

5. The method of claim 3 wherein the first strut nickel titanium alloy layer includes perforations between the first strut soluble core and the exterior of the first strut, and the removing comprises removing the first strut soluble core through the perforations.

6. The method of claim 1 wherein the soluble material is molybdenum, the method further comprising contacting the first strut soluble core with xenon difluoride to form a first strut central void.

7. The method of claim 1 wherein the soluble material is molybdenum and the weld is a nickel, titanium, and molybdenum alloy.

8. The method of claim 1 wherein the soluble material is a molybdenum chromium alloy and the weld is a nickel, titanium, molybdenum, and chromium alloy.

9. The method of claim 1 wherein the first strut and second strut are part of a single sinusoidal wire.