Medical implant such as a stent

• US 10,322,017 B2
• Filed: 01/06/2017
• Issued: 06/18/2019
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Angiomed GmbH & Co. Medizintechnik KG
• Original Assignee: Angiomed GmbH & Co. Medizintechnik KG
• Inventors: Blank, Thiemo
• Primary Examiner(s): Choi, Stephen
• Application Number:
  US15/400,909
• Publication Number:
  US 20170112644A1
• Time in Patent Office: 893 Days
• 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 2230/0006 circular
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: B23K 15/08 Removing material, e.g. by cutting, by hole drilling
• CPC Class Codes: B23K 2101/06 Tubes
• CPC Class Codes: B23K 26/38 by boring or cutting
• CPC Class Codes: B26F 3/004 by means of a fluid jet methods for use of abrasive blasting for cutting B24C1/045; guns for abrasive fluid jets B24C5/02; perforating by non-mechanical means, e.g. by fluid jet B26F1/26

Abstract

A medical implant such as a self-expanding shape memory alloy stent with a strut matrix formed by cut patterns in a wall of a tubular workpiece can be enhanced by arranging for the line of the laser beam when cutting the struts to be one that does not pass through the longitudinal rotational axis of the tubular workpiece. Such “off-axis” cutting can modify the cross-sectional shape and area of each strut, along its length. Such modulation can enhance the fatigue resistance of the stent matrix, or increase the radial force that the stent matrix is capable of exerting on bodily tissue within which it is implanted.

Claims

1. A method of forming a medical implant from a tubular workpiece, the tubular workpiece having a longitudinal axis and a wall defining a lumen along the longitudinal axis, the method comprising

positioning the tubular workpiece in a jet cutting apparatus;

forming a plurality of struts in the tubular workpiece with a beam of the jet cutting apparatus, comprising;

cutting a first portion of the wall along a first line from an abluminal surface of the tubular workpiece to a first line end point, wherein the first line does not intersect the longitudinal axis;

translating the tubular workpiece relative to the beam; and

cutting a second portion of the wall along a second line from the first line end point to a luminal surface of the tubular workpiece, wherein the second line forms a non-zero angle with the first line.

2. The method of claim 1, wherein the first line and the second line together create a multifaceted first flank of a first strut.

3. The method of claim 2, wherein the forming step further comprises cutting a second flank of the first strut in the wall adjacent the first flank, the second flank extending from the abluminal surface to the luminal surface of the tubular workpiece.

4. The method of claim 3, wherein the second flank is multifaceted.

5. The method of claim 3, wherein the first flank and the second flank together create a sharp cutting edge.

6. The method of claim 3, wherein the first strut has a luminal surface area smaller than an abluminal surface area.

7. The method of claim 6, wherein the forming step further comprises cutting a third flank in the wall adjacent the second flank, the second flank and the third flank defining sides of a second strut, wherein the second strut has a luminal surface area larger than an abluminal surface area.

8. The method of claim 1, wherein the medical implant is a stent designed for intraluminal positioning in a patient.

9. The method of claim 1, wherein the beam of the jet cutting apparatus is an electron beam.

10. The method of claim 1, wherein the beam of the jet cutting apparatus is a jet of fluid.

11. The method of claim 1, wherein the beam of the jet cutting apparatus is a laser beam.