IMPLANTABLE AND LUMEN-SUPPORTING STENTS AND RELATED METHODS OF MANUFACTURE AND USE

• US 20160346105A1
• Filed: 08/11/2016
• Published: 12/01/2016
• Est. Priority Date: 10/19/2007
• Status: Active Grant

• Current Assignee: Celonova Biosciences, Inc. (Boston Scientific Corporation)
• Original Assignee: Celonova Biosciences, Inc. (Boston Scientific Corporation)
• Inventors: KARL, Stuart Earl, LEE, Michael J., KING, Riley
• Granted Patent: US 10,327,926 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0029 differing in bending or flexure capacity
• CPC Class Codes: A61F 2250/0031 made from both resorbable and non-resorbable prosthetic parts, e.g. adjacent parts
• CPC Class Codes: A61F 2250/0032 differing in radiographic density
• CPC Class Codes: A61F 2250/0036 differing in thickness
• CPC Class Codes: A61F 2250/0068 the pharmaceutical product being in a reservoir

Abstract

An implantable stent includes multiple circumferential segments that surround a bore and are connected in series along a length to form a tubular wall. Multiple adjacent alternating opposite facing crowns arranged along each segment'"'"'s circumference are bridged by struts. The struts include a series of staggered arcuate edges with limited flats to provide a limited region of maximum width between significantly extended reducing diameter tapers at either end where they transition into the crowns. Connections between adjacent segments are wider and stiffer than the struts and strut-crown transitions in the segments. The crowns include inner and outer radii with off-set centers along a common axis to provide medial crown peaks along the axis that are wider than the narrowed crown shoulders on either side of the axis and from which the tapered struts extend. Material strain and flexure along the stent during lateral bending is distributed mainly within the segments, e.g. along the struts or crowns, versus at the connections between segments. Material strain and deformation during radial expansion is principally concentrated at the crown shoulders and tapered transition region with the struts. Particular closed-open-closed arrangements along the stent length are disclosed, though with fewer stent connections in the relatively “closed” end-portions along the stent than are provided by other typically “open” cell stents in prior use. Enhanced combinations of performance characteristics are provided regarding visibility, trackability, expansion characteristics, fatigue failures, coating integrity, and local drug delivery from the stent.

Claims

1-26. -26. (canceled)

27. An implantable medical stent system, comprising:

a radially expandable stent comprising a filamental structure in a pattern surrounding a bore to form a substantially tubular wall along a length relative to a longitudinal axis;

wherein the filamental structure comprises at least one arcuate crown with a crown peak having a radius of curvature located along a reference axis, and first and second arcuate crown shoulders on first and second sides, respectively, of the reference axis;

wherein the filamental structure also comprises at least one pair of first and second elongated struts extending from the first and second crown shoulders, respectively;

the first and second elongated struts have a region of constant maximum width at an intermediate portion and tapering toward the first and second crown shoulders; and

wherein the arcuate crown peak comprises at least one of (a) a peak width that is greater than at least one of first and second shoulder widths along the first and second respective arcuate crown shoulders, (b) an inner radius of curvature about a second center that is offset from a first center of an outer radius of curvature, and (c) a radial expansion characteristic with a strain distribution that is substantially lower than along at least one of the first and second crown shoulders; and

wherein the filamental structure also comprises a coating on a surface of the filamental structure.

28. The stent system of claim 27, wherein the coating is at least one of a polymer coating, a non-polymer coating, a radiopaque coating, and a metallic coating.

29. The stent system of claim 27, wherein the polymer coating can have zwitterionic pendant groups.

30. The stent system of claim 27, wherein the coating is continuous on the surface of the filamental structure.

31. The stent system of claim 27, wherein the coating is discontinuous on the surface of the filamental structure.

32. The stent system of claim 27, wherein the coating is disposed on an inner surface of the filamental structure.

33. The stent system of claim 27, wherein the coating is disposed on an outer surface of the filamental structure.

34. The stent system of claim 27, wherein the coating is one or more layers.

35. The stent system of claim 27, wherein the coating is bioerodable.

36. The stent system of claim 27, wherein the coating further comprises a bioactive agent.

37. The stent system of claim 36, wherein the bioactive agent is at least one of antineoplastic, antiinflammatory, antiplatelet, anticoagulant, antifibrin, antithrombin, antimitotic, antibiotic, antiproliferative and antioxidant substances, as well as calcium channel blockers, colchicine fibroblast growth factor antagonists, histamine antagonists, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, monoclonal antibodies, phosphodiesterase inhibitors, prostaglandin inhibitors, platelet-derived growth factor antagonists, serotonin inhibitors, steroids, and thioprotease inhibitors.

38. The stent system of claim 36, wherein the bioactive agent is at least one of rapamycin, cladribine, heparin, nitrous oxide, nitric oxide, actinomycin D, alpha-interferon, genetically engineered epithelial cells, fish oil, des-aspartate angiotensin I, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), statins, hormones, and estradiol.

39. The stent system of claim 27, wherein the filamental structure maintains coating integrity.

40. The stent system of claim 36, wherein the bioactive agent elutes from the coating.

41. An implantable medical stent system, comprising:

a radially expandable stent comprising a filamental structure in a pattern surrounding a bore to form a substantially tubular wall along a length relative to a longitudinal axis;

wherein the filamental structure comprises at least one arcuate crown with a crown peak having a radius of curvature located along a reference axis, and first and second arcuate crown shoulders on first and second sides, respectively, of the reference axis;

wherein the filamental structure also comprises at least one pair of first and second elongated struts extending from the first and second crown shoulders, respectively;

the first and second elongated struts have a region of constant maximum width at an intermediate portion and tapering toward the first and second crown shoulders; and

wherein the arcuate crown peak comprises at least one of (a) a peak width that is greater than at least one of first and second shoulder widths along the first and second respective arcuate crown shoulders, (b) an inner radius of curvature about a second center that is offset from a first center of an outer radius of curvature, and (c) a radial expansion characteristic with a strain distribution that is substantially lower than along at least one of the first and second crown shoulders; and

wherein the filamental structure also comprises a polymer coating on a surface of the filamental structure.

42. The stent system of claim 41, wherein the polymer coating further comprises a bioactive agent.

43. The stent system of claim 41, wherein the coating is continuous on the surface of the filamental structure.

44. The stent system of claim 41, wherein the coating is disposed on an inner surface of the filamental structure.

45. The stent system of claim 41, wherein the coating is disposed on an outer surface of the filamental structure.

46. An implantable medical stent system, comprising:

a radially expandable stent comprising a filamental structure in a pattern surrounding a bore to form a substantially tubular wall along a length relative to a longitudinal axis;

wherein the filamental structure comprises at least one arcuate crown with a crown peak having a radius of curvature located along a reference axis, and first and second arcuate crown shoulders on first and second sides, respectively, of the reference axis;

wherein the filamental structure also comprises at least one pair of first and second elongated struts extending from the first and second crown shoulders, respectively;

the first and second elongated struts have a region of constant maximum width at an intermediate portion and tapering toward the first and second crown shoulders; and

wherein the arcuate crown peak comprises at least one of (a) a peak width that is greater than at least one of first and second shoulder widths along the first and second respective arcuate crown shoulders, (b) an inner radius of curvature about a second center that is offset from a first center of an outer radius of curvature, and (c) a radial expansion characteristic with a strain distribution that is substantially lower than along at least one of the first and second crown shoulders; and

wherein the filamental structure also comprises a polymer coating comprising a bioactive agent on a surface of the filamental structure.