MEDICAL DEVICES WITH AMORPHOUS METALS, AND METHODS THEREFOR

• US 20080125848A1
• Filed: 06/29/2007
• Published: 05/29/2008
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Inventors: Kusleika, Richard S., Kravik, Rick
• Granted Patent: US 8,057,530 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61L 29/02 Inorganic materials
• CPC Class Codes: A61L 29/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque

Abstract

Medical devices made at least in part of amorphous metals or alloys are provided. Certain embodiments include filters, stents, guidewires, snares, and coils comprised of amorphous metal. Methods of forming the medical devices, including methods of shape setting amorphous metals or alloys into components of medical devices are also provided. Methods of using amorphous metal medical devices are also provided.

Claims

1. A medical device comprising an amorphous metal, wherein the medical device is a shape set medical device.

2. The medical device of claim 1, wherein the medical device is a filter.

3. The medical device of claim 2, wherein the filter is a braided filter.

4. The medical device of claim 1, wherein the medical device is a stent.

5. The medical device of claim 4, wherein the stent is self expanding.

6. The medical device of claim 4, wherein the stent is balloon expandable.

7. The medical device of claim 1, wherein the medical device is a stent delivery system.

8. The medical device of claim 1, wherein the medical device is a guidewire.

9. The medical device of claim 1, wherein the medical device is a snare.

10. The medical device of claim 1, wherein the medical device is a coil.

11. The medical device of claim 1, wherein the medical device is a catheter.

12. The medical device of claim 1, wherein the medical device is a septal defect closure device.

13. The medical device of claim 1, wherein the medical device is a left atrial appendage closure device.

14. The medical device of claim 1, wherein the medical device is a staple.

15. The medical device of claim 1, wherein the medical device is a clip.

16. The medical device of claim 1, wherein the medical device comprises one or more amorphous metal filaments having a diameter between about 0.010 inches (0.25 mm) about 0.00050 inches (0.013 mm).

17. The medical device of claim 1, wherein the medical device further comprises a coating on at least a portion of the amorphous metal.

18. The medical device of claim 17, wherein the coating comprises one or more of a radiopaque coating, a drug coating, an active agent release coating, a biocompatible coating, or a lubricious coating.

19. The medical device of claim 1, wherein the medical device is sufficiently corrosion resistant to be internally biocompatible.

20. The medical device of claim 1, wherein the medical device is capable of imaging under MRI.

21. The medical device of claim 1, wherein the medical device comprises amorphous and crystalline portions.

22. The medical device of claim 1, wherein the medical device is capable of sustaining between about 0.5 volume percent to about 75 volume percent conversion of the amorphous metal into crystalline metal under storage or sterilization temperatures of less than 60°

C. for a period of 2 years.

23. The medical device of claim 22, wherein less than 40 volume percent of the amorphous metal is converted to crystalline metal.

111. A method of using the snare of claim 10 comprising delivering the snare to a blood vessel.

24. A method of forming a medical device or a component thereof comprising:

shape setting a structure comprising an amorphous metal into the medical device or the component.

25. The method of claim 24, wherein the step of shape setting comprises heating a structure comprising an amorphous metal to an elevated temperature sufficient to shape-set the structure with the structure continuing to comprise an amorphous metal.

26. The method of claim 24, wherein the step of shape setting comprises:

providing the structure; and

expanding the structure into a first expanded structure on a mandrel.

27. The method of claim 26, wherein the step of shape setting further comprises:

annealing at least a portion of the first expanded structure at a temperature about or above the glass transition temperature of the amorphous metal.

28. The method of claim 27, wherein the step of annealing causes the first expanded structure to maintain the expanded shape.

29. The method of claim 27, wherein the step of annealing is configured to convert at least a portion of the amorphous metal of the first expanded structure into crystalline metal.

30. The method of claim 27, further comprising expanding at least some portion of the first expanded structure to form a second expanded structure.

31. The method of claim 30, further comprising annealing at least a portion of the second expanded structure at a temperature of about or above the glass transition temperature of the amorphous metal.

32. The method of claim 24, wherein the step of shape setting comprises expanding at least a portion of the structure and annealing the structure at about or above the glass transition temperature of the amorphous metal.

33. The method of claim 32, wherein the glass transition temperature of the amorphous metal is greater than 140°

F. (60°

C.).

34. The method of claim 32, wherein the glass transition temperature of the amorphous metal is greater than 160°

F. (71°

C.).

35. The method of claim 32, wherein the glass transition temperature of the amorphous metal is greater than 180°

F. (82°

C.).

36. The method of claim 24, wherein the step of shape setting comprises:

converting about 5 to about 75 volume percent of the amorphous metal to a crystalline metal.

37. The method of claim 24, wherein the step of shape setting comprises:

converting about 10 to about 62 volume percent of the amorphous metal to a crystalline metal.

38. The method of claim 24, wherein the step of shape setting comprises:

converting about 15 to about 40 volume percent of the amorphous metal to a crystalline metal.

39. The method of claim 24, wherein the structure is selected from the group consisting of a tube, a cylinder, one or more wires, one or more strands, and one or more ribbons.

40. The method of claim 24, comprising shape setting the device into a filter.

41. The method of claim 40, comprising shape setting the device into a braided filter.

42. The method of claim 24, comprising shape setting the device into a stent.

43. The method of claim 42, wherein the stent is self expanding.

44. The method of claim 42, wherein the stent is balloon expandable.

45. The method of claim 24, comprising shape setting the device into a stent delivery system.

46. The method of claim 24, comprising shape setting the device into a guidewire.

47. The method of claim 24, comprising shape setting the device into a snare.

48. The method of claim 24, comprising shape setting the device into a coil.

49. The method of claim 24, comprising shape setting the device into a catheter.

50. The method of claim 24, comprising shape setting the device into a septal defect closure device.

51. The method of claim 24, comprising shape setting the device into a left atrial appendage closure device.

52. The method of claim 24, comprising shape setting the device into a staple.

53. The method of claim 24, comprising shape setting the device into a clip.

54. A method of using a medical device comprising:

inserting a shape set medical device comprising amorphous metal in a body lumen.

55. The method of claim 54, further comprising:

delivering the shape set medical device into the body lumen in a collapsed configuration; and

expanding the shape set medical device in the body lumen.

56. The method of claim 54, wherein the shape set medical device is a stent.

57. The method of claim 56, wherein the stent is self-expanding.

58. The method of claim 56, wherein the stent is balloon-expandable.

59. The method of claim 54, wherein the shape set medical device is a filter.

60. The method of claim 59, wherein the filter comprises amorphous metal filaments.

61. The method of claim 60, wherein the amorphous metal filaments are braided.

62. The method of claim 54, wherein the medical device is a snare.

63. The method of claim 54, further comprising:

treating a treatment site with the shape set medical device.

64. The method of claim 54, further comprising:

withdrawing the shape set medical device from the body lumen.

65. A medical device comprising a portion, wherein the portion comprises a partially amorphous and partially crystalline metal.

66. The medical device of claim 65, wherein the medical device is a filter.

67. The medical device of claim 66, wherein the filter is a braided filter.

68. The medical device of claim 65, wherein the medical device is a stent.

69. The medical device of claim 68, wherein the stent is self expanding.

70. The medical device of claim 68, wherein the stent is balloon expandable.

71. The medical device of claim 65, wherein the medical device is a stent delivery system.

72. The medical device of claim 65, wherein the medical device is a guidewire.

73. The medical device of claim 65, wherein the medical device is a snare.

74. The medical device of claim 65, wherein the medical device is a coil.

75. The medical device of claim 65, wherein the medical device is a catheter.

76. The medical device of claim 65, wherein the medical device is a septal defect closure device.

77. The medical device of claim 65, wherein the medical device is a left atrial appendage closure device.

78. The medical device of claim 65, wherein the medical device is a staple.

79. The medical device of claim 65, wherein the medical device is a clip.

80. A method of forming the medical device of claim 65, the method comprising:

providing a structure comprising an amorphous metal;

converting the structure into a partially crystalline structure, wherein the partially crystalline structure is the medical device.

81. The method of claim 80, wherein the step of converting comprising heating the structure in a manner sufficient to converting at least some of the amorphous metal to crystalline metal.

82. The method of claim 81, further comprising heating the structure to a temperature about or above the glass transition temperature of the amorphous metal.

83. A method of using the medical device of claim 65 comprising inserting the medical device into a body lumen.

84. The method of claim 83, further comprising

delivering the medical device into the body lumen in a collapsed configuration;

and

expanding the shape set medical device in the body lumen.

85. A guidewire comprising amorphous metal.

86. The guidewire of claim 85, wherein the guidewire is monofilament, wherein the monofilament comprises amorphous metal.

87. The guidewire of claim 85, wherein the guidewire is multi-stranded, wherein one or more of a strand or filament of the multi-stranded guidewire comprises amorphous metal.

88. A method of using the guidewire of claim 85 comprising:

inserting the guidewire in a body lumen.

89. A stent delivery system comprising an amorphous metal structure.

90. The stent delivery system of claim 89, wherein the amorphous metal structure is a stylet.

91. The stent delivery system of claim 89, wherein the amorphous metal structure is a reinforcing element.

92. The stent delivery system of claim 89, wherein the stent delivery system is an over the wire system.

93. The stent delivery system of claim 89, wherein the stent delivery system is a rapid exchange system.

94. The stent delivery system of claim 89, wherein the stent delivery system is a fixed wire system.

95. The stent delivery system of claim 89, wherein the stent delivery system comprises a self expanding or a balloon expandable stent.

96. The stent delivery system of claim 95, wherein the self expanding or the balloon expandable stent comprises amorphous metal.

97. The stent delivery system of claim 95, wherein the self expanding or the balloon expandable stent comprises a shape set amorphous metal.

98. A method of using the stent delivery system of claim 89 comprising:

inserting a portion of the system in a patient; and

delivering a stent to a blood vessel;

expanding the stent to the walls of the blood vessel.

99. A medical filter comprising amorphous metal.

100. The filter of claim 99, wherein the filter is an embolic protection filter.

101. The filter of claim 99, wherein the filter comprises a wire frame, at least a portion of the wire frame comprises an amorphous metal.

102. The filter of claim 99, wherein the filter comprises a filter element comprising amorphous metal filaments.

103. The filter of claim 102, wherein the filter element is braided.

104. The filter of claim 102, wherein the filter has a pore size ranging from about 10 to about 1000 microns.

105. The filter of claim 102, wherein the filter has a pore size ranging from about 20 to about 500 microns.

106. The filter of claim 102, wherein the filter has a pore size ranging from about 30 to about 250 microns.

107. The filter of claim 102, wherein the filter has a pore size ranging from about 40 to about 150 microns.

108. The filter of claim 102, wherein the filter has a pore size ranging from about 50 to about 100 microns.

109. A method of using the filter of claim 99 comprising delivering the filter to a blood vessel.

110. A snare comprising amorphous metal.

112. A coil comprising amorphous metal.

113. A method of using the coil of claim 112 comprising delivering the coil to a blood vessel.

114. A catheter comprising amorphous metal.

115. A method of using the catheter of claim 114 comprising inserting a portion of the catheter in a patient.

116. A closure medical device comprising amorphous metal.

117. The closure medical device of claim 116, wherein the closure medical device is a septal defect closure device.

118. The closure medical device of claim 116, wherein the closure medical device is a left atrial appendage closure device.

119. A method of using the closure medical device of claim 117 comprising delivering the septal defect closure device to a septal defect.

120. A method of using the closure medical device of claim 118 comprising delivering the left atrial appendage closure device to a left atrial appendage.

121. A medical staple comprising amorphous metal.

122. A medical clip comprising amorphous metal.

123. A medical device comprising an at least partially amorphous metal surface, wherein the at least partially amorphous metal surface has improved corrosion resistance when the at least partially amorphous metal surface is compared to a more crystalline metal surface, wherein the medical device is selected from the group consisting of a filter, a catheter, a snare, a coil, a closure device, a medical staple, and a medical clip.

124. A medical device comprising a structure comprising amorphous metal, wherein the structure has one or more of improved MRI safety or improved MRI compatibility when compared to a more crystalline metal surface, wherein the medical device is selected from the group consisting of a filter, a catheter, a snare, a coil, a closure device, a medical staple, and a medical clip.

125. A method of forming a stent comprising:

providing a foil of amorphous metal;

forming the foil into a tube having a seam;

etching the tube to form a medical stent comprising a plurality of longitudinal segments.

126. The method of claim 125, wherein the step of providing the foil comprises:

cooling a molten metal or alloy in a manner configured to produce a substantially amorphous metal foil.

127. The method of claim 125, wherein the step of etching comprises:

chemically etching the tube at a temperature lower than the glass transition temperature of the amorphous metal.

128. The method of claim 125, wherein the step of etching comprises:

chemically etching the tube in a manner configured to prevent the substantial crystallization of the amorphous metal.

129. The method of claim 125, wherein the stent has a wall thickness between about 0.00050 inches (0.013 mm) to about 005 inches (0.13 mm).

130. The method of claim 125, wherein the stent has a wall thickness between about 0.00080 inches (0.013 mm) to about 0015 inches (0.13 mm).

131. A method of forming a stent comprising:

depositing a foil comprising amorphous metal around a substrate; and

removing at least part of the substrate from the foil to form a stent.

132. The method of claim 131, wherein the step of depositing comprises vapor depositing the foil.

133. The method of claim 131, wherein the step of removing comprises etching at least part of the substrate.

134. The method of claim 131, wherein the step of removing comprises dissolving at least part of the substrate.

135. The method of claim 131, wherein the step of removing is configured to prevent the substantial crystallization of the amorphous metal.

136. The method of claim 131, wherein the substrate is substantially cylindrical.

137. The method of claim 131, wherein the substrate is a stent skeleton.

138. A method of forming a stent comprising:

providing a tube comprising amorphous metal;

cutting one or more openings in the tube to form a stent by a heat generating process, the heat generating process configured to substantially minimize crystallization of the amorphous metal.

139. The method of claim 138, wherein the step of cutting comprises one or more heat generation processes selected from laser machining or electrostatic discharge machining.

140. The method of claim 138, further comprising removing metal adjacent to the one or more openings by a cutting process.

141. The method of claim 138, wherein the cutting process is selected from one or more of chemical etching or microblasting at a temperature lower than the glass transition temperature of the amorphous metal.

142. A medical device comprising an amorphous metal structure, wherein the medical device is coated with one or more selected from the group consisting of a radiopaque coating, a drug coating, an active agent release coating, a biocompatible coating, or a lubricious coating.

143. The medical device of claim 142, wherein the medical device is one or more selected from the group consisting of wherein the medical device is selected from the group consisting of a filter, a catheter, a snare, a coil, a closure device, a medical staple, and a medical clip.

144. A method of forming an amorphous metal filter comprising braiding one or more wire strands comprising an amorphous metal into a braided structure.

145. The method of claim 144, further comprising molding the braided structure into a filter body.

146. The method of claim 145, wherein the step of molding comprises applying axial tension to the braided structure against a mandrel.

147. The method of claim 146, wherein the mandrel comprises a proximal projection for forming one or more proximal openings in the filter body.

148. The method of claim 146, wherein the one or more wire strands project about the periphery of the projection.

149. The method of claim 144, further comprising fixing the lengths of the one or more wire strands, thereby causing the filter body to retain a shape.

150. The method of claim 145, wherein the step of molding comprises:

heating the filter body to a temperature of about or above the glass transition temperature of the amorphous metal.

151. The method of claim 150, wherein the step of heating is configured to substantially prevent conversion of the amorphous metal to a crystalline metal.

152. The method of claim 150, wherein the step of heating is configured to cause at least partial conversion of the amorphous metal to a crystalline metal.

153. The method of claim 150, wherein the step of heating is configured to cause complete conversion of the amorphous metal to a crystalline metal.