Method of making stents with radiopaque markers

• US 8,752,268 B2
• Filed: 08/09/2013
• Issued: 06/17/2014
• Est. Priority Date: 05/26/2006
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Inventors: Wu, Patrick P.
• Primary Examiner(s): COZART, JERMIE E
• Application Number:
  US13/964,008
• Publication Number:
  US 20130325106A1
• Time in Patent Office: 312 Days
• Field of Search: 623/1.34, 294/58, 295/08, 295/16, 295/17
• US Class Current: 29/458
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• CPC Class Codes: A61F 2002/91566 connected trough to trough
• CPC Class Codes: A61F 2002/91583 by a bridge, whereby at least one of its ends is connected along the length of a strut between two consecutive apices within a band
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61L 29/00 Materials for catheters, medical tubing, cannulae, or endoscopes or for coating catheters shape or structure of catheters A61M25/00
• CPC Class Codes: A61L 31/04 Macromolecular materials
• CPC Class Codes: A61L 31/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: B29C 65/48 : using adhesives , i.e. using supplementary joining material; solvent bonding
• CPC Class Codes: B29D 23/00 : Producing tubular articles B29D24/00 takes precedence
• CPC Class Codes: B29L 2031/7543 : Balloon catheters
• CPC Class Codes: C08L 67/04 : Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: Y10T 156/1034 : Overedge bending of lamina about edges of sheetlike base
• CPC Class Codes: Y10T 29/49885 : with coating before or during assembling
• CPC Class Codes: Y10T 29/49913 : by constricting outer annulus
• CPC Class Codes: Y10T 29/49927 : Hollow body is axially joined cup or tube
• CPC Class Codes: Y10T 29/49929 : Joined to rod
• CPC Class Codes: Y10T 29/49993 : Filling of opening

Abstract

Various embodiments of stents with radiopaque markers arranged in patterns are described herein.

Claims

1. A method of crimping a stent on a balloon, comprising:

(a) providing a biodegradable polymeric stent, wherein the material from which structural elements of the stent are made consist of poly(l-lactide) and a second, different polymer (“

PLLA-based polymer”

);

(b) attaching markers to the polymeric stent to provide capability of obtaining images of the PLLA-based polymer stent with an imaging device during and after implantation of the stent in a vessel,

wherein the stent consists of two pairs of markers, two of the markers being attached in an adjacent configuration about a proximal most end ring of the stent, and the remaining two markers being attached in an adjacent configuration about a distal most end ring of the stent, with the proviso that the stent has no other markers but for the four markers to allow for imaging of the PLLA-based polymer stent and with a further proviso that an entire length of the stent between the first pair and second pair of markers is devoid of any markers,

wherein a center point of a first marker is positioned at a circumferential distance from a center point of its adjacent second marker,

wherein a center point of a third marker is positioned at a circumferential distance from a center point of its adjacent fourth marker, and

wherein the pair of markers about the proximal most end ring of the polymeric stent are circumferentially off-set from the pair of markers about the distal most end ring of the polymeric stent; and

(c) crimping the stent on a balloon of a catheter assembly by application of a crimping pressure to the stent positioned over the balloon,

wherein when the crimping pressure is applied to the stent, the stent has regions of low strain and regions of high strain, such that PLLA-based elements to which each pair of marker is attached are regions of low strain, and

wherein the PLLA-based elements of the markers do not compromise the mechanical integrity of the stent.

2. A method of crimping a stent on a balloon, comprising:

(a) providing a biodegradable polymeric stent, wherein the material from which structural elements of the stent are made consist of poly(D, L-lactide) or poly (D, L-lactic acid) (PDLLA);

(b) attaching markers to the polymeric stem to provide capability of obtaining images of the polymeric stent with an imaging device during and after implantation of the stent in a vessel,

wherein the stent consists of two pairs of markers, two of the markers being attached in an adjacent configuration about a proximal most end ring of the stent, and the remaining two markers being attached in an adjacent configuration about a distal most end ring of the stent, with the proviso that the stent has no other markers but for the four markers to allow for imaging of the polymeric stent and with a further proviso that an entire length of the stem between the first pair and second pair of markers is devoid of any markers,

wherein a center point of a first marker is positioned at a circumferential distance from a center point of its adjacent second marker,

wherein a center point of a third marker is positioned at a circumferential distance from a center point of its adjacent fourth marker, and

wherein the pair of markers about the proximal most end ring of the polymeric stent are circumferentially off-set from the pair of markers about the distal most end ring of the polymeric stent; and

(c) crimping the stent on a balloon of a catheter assembly by application of a crimping pressure to the stent positioned over the balloon,

wherein when the crimping pressure is applied to the stent, the stent has regions of low strain and regions of high strain, such that PDLLA elements to which each pair of marker is attached are regions of low strain, and

wherein the PDLLA elements of the markers do not compromise the mechanical integrity of the stent.

3. A method of crimping a stent on a balloon, comprising:

(a) providing a biodegradable polymeric stent, wherein the material from which structural elements of the stent are made consists of a lactide or lactic acid polymer (“

lactide-based polymer”

);

(b) attaching markers to the lactide-based polymeric stent to provide capability of obtaining images of the lactide-based polymeric stent with an imaging device during and after implantation of the stent in a vessel,

wherein the stent consists of two pairs of markers, two of the markers being attached in an adjacent configuration about a proximal most end ring of the stent, and the remaining two markers being attached in an adjacent configuration about a distal most end ring of the stent, with the proviso that the stent has no other markers but for the four markers to allow for imaging of the lactide-based polymeric stent and with a further proviso that an entire length of the stent between the first pair and second pair of markers is devoid of any markers,

wherein a center point of a first marker is positioned at a circumferential distance from a center point of its adjacent second marker,

wherein a center point of a third marker is positioned at a circumferential distance from a center point of its adjacent fourth marker, and

wherein the pair of markers about the proximal most end ring of the polymeric stent are circumferentially off-set from the pair of markers about the distal most end ring of the polymeric stent; and

(c) crimping the stent on a balloon of a catheter assembly by application of a crimping pressure to the stent positioned over the balloon,

wherein when the crimping pressure is applied to the stent, the stent has regions of low strain and regions of high strain, such that lactide-based elements to which each pair of marker is attached are regions of low strain, and

wherein the lactide-based elements of the markers do not compromise the mechanical integrity of the stent.