Ablation catheter

• US 20060089637A1
• Filed: 07/12/2005
• Published: 04/27/2006
• Est. Priority Date: 10/14/2004
• Status: Abandoned Application

• Current Assignee: Medtronic Ablation Frontiers LLC (Medtronic Plc)
• Original Assignee: Medtronic Ablation Frontiers LLC (Medtronic Plc)
• Inventors: Flaherty, J. Christopher, Werneth, Randell L., Currie, Gary Edward, Sherman, Marshall L., Castellano, Thomas M.
• Application Number:
  US11/179,333
• Publication Number:
  US 20060089637A1
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 18/16 Indifferent or passive electrodes for grounding
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/00291 using suction
• CPC Class Codes: A61B 2018/00351 Heart
• CPC Class Codes: A61B 2018/1467 using more than two electrodes on a single probe

Abstract

Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter which has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition.

Claims

1. An ablation catheter, comprising:

(a) an elongated, flexible, tubular body member having a proximal end, a distal end and a lumen extending therebetween;

(b) a control shaft coaxially disposed and slidingly received within the lumen of the Tubular Body Member;

(c) a flexible carrier assembly which includes at least one ablation element used to deliver energy to tissue; and

(d) a coupler which connects the control shaft to the carrier assembly;

wherein retraction of the control shaft causes the carrier assembly to be constrained within the lumen of the tubular body member; and

wherein advancement of the control shaft causes the carrier assembly to extend beyond the distal end of the tubular body member.

2. The catheter of claim 1 wherein the control shaft can be completely removed from the lumen of the tubular body member.

3. The catheter of claim 1 further comprising a visualization marker surrounding the tubular body member near the distal end of said tubular body member.

6. The catheter of claim 3 wherein the band transmits energy.

7. The catheter of claim 3 wherein the band is an antenna.

8. The catheter of claim 3 wherein the band facilitates the storage of energy

9. The catheter of claim 8 wherein the band provides a capacitive storage of energy.

14. The catheter of claim 1 wherein the tubular body member includes means to deflect the distal end of said tubular body member.

21. The catheter of claim 1 wherein the tubular body member includes at least two pull wires used to deflect the distal end of said tubular body member.

22. The catheter of claim 21 wherein a first pull wire causes bending at a first deflection point and a second pull wire causes bending at a second deflection point.

23. The catheter of claim 1 wherein the tubular member further comprises a first segment with a specific flexibility and a second segment with a different flexibility, such that the pull wire causes said first segment to bend at a radius different than said second segment.

30. The catheter of claim 1 wherein the ablation catheter includes means to deflect the distal end of said control shaft.

31. The catheter of claim 30 wherein the ablation catheter further includes means to deflect the distal end of said tubular body member.

41. The catheter of claim 1 wherein the carrier assembly is configured to be engaged over an endocardial surface to map and/or ablate tissue on said surface.

42. The catheter of claim 1 wherein the carrier assembly includes a plurality of resilient arms, each arm having a proximal arm segment and a distal arm segment resiliently or rotatably joined to each other at a bend point.

45. The catheter of claim 1 wherein the carrier assembly is more flexible than the control shaft.

46. The catheter of claim 1 wherein the carrier assembly has a pre-determined shape such that advancement of the control shaft causes said carrier assembly to expand to said pre-determined shape as said carrier assembly extends beyond the distal end of the tubular body member.

47. The catheter of claim 46 wherein the pre-determined shape is a spiral shape.

48. The catheter of claim 46 wherein the pre-determined shape includes multiple loops that approximate a single plane.

49. The catheter of claim 46 wherein the pre-determined shape includes multiple loops that lie in multiple planes.

50. The catheter of claim 46 wherein the predetermined shape includes at least three arms, each of said arms extending radially outward from the central axis of the distal end of the tubular body member.

51. The catheter of claim 50 wherein one or more arms includes one or more electrodes, said one or more electrodes being between 1 and 4 millimeters in length.

52. The catheter of claim 46 wherein the pre-determined shape includes four or more arms, each of said arms extending radially outward from the central axis of the distal end of the tubular body member.

53. The catheter of claim 52 wherein one or more arms includes one or more electrodes, said one or more electrodes being between 1 and 4 millimeters in length.

54. The catheter of claim 53 wherein the pre-determined shape is an umbrella shape.

55. The catheter of claim 54 wherein the umbrella shape includes two arms extending radially outward from the central axis of the distal end of the tubular body member.

56. The catheter of claim 55 wherein at least one of the arms is void of ablation elements.

57. The catheter of claim 54 wherein the umbrella shape includes at least three arms extending radially outward from the central axis of the distal end of the tubular body member.

58. The catheter of claim 57 wherein at least one of the arms is void of ablation elements.

59. The catheter of claim 46 wherein the pre-determined shape is a pattern of petaloids.

60. The catheter of claim 1 wherein the carrier assembly includes a midsection including one or more ablation elements, said midsection including a support portion at each end.

61. The catheter of claim 60 wherein either support portion is more rigid than the midsection.

62. The catheter of claim 60 wherein the midsection has a pre-determined bowed shape.

63. The catheter of claim 62 wherein the bowed portion extends radially outward from distal end of the tubular body member.

64. The catheter of claim 62 wherein the bowed portion extends radially inward toward the distal end of the tubular body member.

74. The catheter of claim 1 wherein the carrier assembly includes two carrier arm bend points.

75. The catheter of claim 74 wherein a carrier arm bend point includes approximately a ninety degree bend.

76. The catheter of claim 75 wherein a carrier arm bend point is a spring.

79. The catheter of claim 1 wherein the carrier assembly includes one or more segments with a non-circular cross-section.

80. The catheter of claim 79 wherein the non-circular cross-section is selected from the group consisting of:

oval;

rectangular;

trapezoidal;

parallelepiped; and

combinations thereof.

81. The catheter of claim 80 wherein the non-circular cross-section portion causes the carrier assembly to bend in one ore more preferred directions.

82. The catheter of claim 1 wherein the carrier assembly comprises two or more wires.

83. The catheter of claim 82 wherein two or more wires each include one or more ablation elements.

84. The catheter of claim 82 wherein two or more wires are attached to the coupler.

85. The catheter of claim 84 wherein the two or more wires form petaloid shaped arcs.

86. The catheter of claim 1 wherein the ablation element is an electrode.

87. The catheter of claim 1 wherein the ablation element includes elements selected from the group consisting of:

wire coils;

conductive plates;

semiconductor plates; and

combinations thereof.

88. The catheter of claim 87 wherein the semiconductor plates further include embedded circuitry.

89. The catheter of claim 88 wherein the embedded circuitry perform one or more functions selected from the group consisting of:

electromagnetic sensing;

modified energy delivery;

pulse width modulated energy delivery;

temperature sensing;

physiologic sensing;

signal processing and closed loop energy delivery.

90. The catheter of claim 1 further comprising a second ablation element.

91. The catheter of claim 90 wherein each ablation element can be independently controlled to deliver energy.

92. The catheter of claim 91 wherein the first ablation element and second ablation element can deliver energy simultaneously.

93. The catheter of claim 90 wherein the first ablation element and the second ablation element are connected serially.

94. The catheter of claim 90 wherein the second ablation element is powered after the first ablation element is powered.

95. The catheter of claim 94 wherein the second ablation element is powered after the first ablation element reaches a pre-determined temperature.

96. The catheter of claim 95 wherein the conductivity of the first ablation element significantly increases when said first ablation element reaches the predetermined temperature.

97. The catheter of claim 90 wherein the carrier assembly has a pre-determined shape that includes one or more spiral loops, and two or more ablation elements are located along a single spiral loop.

99. The catheter of claim 1 further comprising two or more additional ablation elements.

100. The catheter of claim 99 comprising one or more wires extending from the proximal end of the tubular body member, said wires transmitting the energy to be delivered by the ablation elements.

101. The catheter of claim 100 wherein the number of delivery wires is less than the number of ablation elements.

102. The catheter of claim 99 wherein a first ablation element delivers one form of energy and a second ablation element delivers a different form of energy.

103. The catheter of claim 102 wherein the first ablation element delivers RF energy and the second ablation element delivers ultrasound energy.

108. The catheter of claim 1 wherein the ablation element is approximately two to eight millimeters long.

109. The catheter of claim 1 wherein the ablation element is a drug delivery device delivering chemical energy.

110. The catheter of claim 109 wherein the drug delivery device includes one or more needles.

111. The catheter of claim 1 wherein the ablation element is also a sensor.

112. The catheter of claim 111 wherein the ablation element can sense one or more parameters selected from the group of:

chemical activity;

light;

electrical activity;

pH;

temperature;

pressure;

fluid flow or other physiologic parameter.

113. The catheter of claim 111 wherein the sensor is used to map electrical activity.

114. The catheter of claim 111 wherein the sensor comprises a thermocouple.

115. The catheter of claim 114 wherein ablation energy delivery is ceased when information received from the thermocouple is one or more of:

higher than a threshold, lower than a threshold such as lower than expected body temperature;

or when the information is unavailable such as when the thermocouple is non-functional.

116. The catheter of claim 1 wherein the delivered energy is selected from the group consisting of:

sound energy such as acoustic energy and ultrasound energy;

electromagnetic energy such as electrical, magnetic, microwave and radiofrequency energies;

thermal energy such as heat and cryogenic energies;

chemical energy;

light energy such as infrared and visible light energies;

mechanical energy;

radiation; and

combinations thereof.

117. The catheter of claim 116 wherein the energy consists of two or more types of energy.

118. The catheter of claim 116 wherein the energy delivered is electrical energy.

119. The catheter of claim 118 wherein the electrical energy is delivered using monopolar;

bipolar; and

a combination of monopolar and bipolar means.

120. The catheter of claim 119 wherein the electrical energy is delivered using both monopolar and bipolar energy delivered sequentially.

121. The catheter of claim 119 wherein the monopolar energy delivery is followed by bipolar energy delivery which is then followed by a period of zero energy delivery.

122. The catheter of claim 121 wherein the three phases of delivery are of equal time duration.

123. The catheter of claim 1 wherein a single ablation element delivers more than one type of energy.

124. The catheter of claim 1 wherein the tissue is cardiac tissue.

125. The catheter of claim 124 wherein the cardiac tissue is atrial wall tissue.

126. The catheter of claim 125 wherein the atrial wall tissue is left atrial wall tissue.

127. The catheter of claim 1 wherein the tissue is selected from the group consisting of:

prostate;

brain;

gall bladder;

uterus;

tumor; and

combinations thereof.

129. The catheter of claim 1 wherein the coupler includes an anti-rotation groove that mates with a projection extending radially inward from a wall of the tubular body member.

130. The catheter of claim 1 wherein the coupler includes an anti-rotation projection that mates with a groove extending radially outward from the inside wall of the tubular body member.

133. The catheter of claim 1 wherein coupler comprises a hollow cylinder with an inside wall and an outside wall, and wherein the carrier assembly includes one or more arms which are mounted to said outside wall of said cylinder.

134. The catheter of claim 133 wherein the carrier assembly further includes one or more arms which are mounted to the inside wall of the cylinder.

135. The catheter of claim 1 wherein the coupler comprises a hollow cylinder with an inside wall and an outside wall, and wherein the carrier assembly includes arms which are mounted to said inside wall of said cylinder.

136. The catheter of claim 135 wherein the carrier assembly further includes one or more arms mounted to the inside wall of the tubular body member.

137. The catheter of claim 1 wherein the coupler provides an electrical connection between wires extending from the proximal end of said catheter and wires extending from the carrier assembly.

138. The catheter of claim 1 wherein the retraction of the control shaft causes the carrier assembly to collapse inward as said carrier assembly is constrained within the lumen of the tubular body member

150. The catheter of claim 1 further comprising one or more sensing elements.

151. The catheter of claim 150 wherein the sensing element measure one or more of:

chemical activity, light, electrical activity, pH, temperature, pressure, fluid flow or other physiologic parameter.

152. The catheter of claim 150 wherein the sensing element is used to map electrical activity.

153. The catheter of claim 150 wherein the sensing element includes a thermocouple used to measure temperature.

161. A system comprising the ablation catheter of claim 1, said system further comprising a heat sensing device.

162. The system of claim 161 wherein the heat sensing device is placed in the esophagus.

163. The system of claim 161 wherein the energy delivered is reduced when the heat sensing device detects a temperature above a pre-determined threshold.

164. The system of claim 163 wherein the threshold is adjustable.

165. A system comprising the ablation catheter of claim 1, said system further comprising an energy delivery apparatus that provides the energy to be delivered to the tissue.

166. The system of claim 165 wherein the ablation catheter further comprises an embedded ID.

167. The system of claim 166 wherein the ID is uploaded by the energy source.

168. The system of claim 167 wherein the ID corresponds to specific parameters for the energy source.

169. The system of claim 166 wherein the ID is embedded in one or more of the control shaft;

the connector; and

the carrier assembly.

170. The system of claim 169 wherein the ablation catheter further comprises a handle.

171. The system of claim 170 wherein the ID is embedded in the handle.

172. The system of claim 165 wherein the energy provided includes a first energy type and a second energy type.

173. The system of claim 172 wherein the first energy type and the second energy type are selected from the group consisting of:

sound energy such as acoustic energy and ultrasound energy;

electromagnetic energy such as electrical, magnetic, microwave and radiofrequency energies;

thermal energy such as heat and cryogenic energies;

chemical energy;

light energy such as infrared and visible light energies;

mechanical and physical energy;

radiation; and

combinations thereof.

4-5. -5. (canceled)

10-13. -13. (canceled)

15-20. -20. (canceled)

24-29. -29. (canceled)

32-40. -40. (canceled)

43-44. -44. (canceled)

65-73. -73. (canceled)

77-78. -78. (canceled)

98. (canceled)

104-107. -107. (canceled)

128. (canceled)

131-132. -132. (canceled)

139-149. -149. (canceled)

154-160. -160. (canceled)

174. An ablation catheter, comprising:

an elongated, flexible, tubular body member having a proximal end, a distal end and a lumen extending therebetween;

a control shaft coaxially disposed and slidingly received within the lumen of the tubular body member;

a flexible carrier assembly mechanically attached to the control shaft, said carrier assembly including at least one ablation element used to deliver energy to tissue, said carrier assembly further comprising one or more flexible arms, each arm with a proximal portion, a distal portion and a hinged portion therebetween;

wherein said proximal portion is attached to the distal end of the tubular body member and said distal portion is attached to the control shaft;

wherein retraction of the control shaft causes the carrier assembly to collapse inwardly such that the distal portion of the carrier assembly is constrained within the lumen of the tubular body member prior to the mid portion being constrained; and

wherein advancement of the control shaft causes the carrier assembly to extend beyond the distal end of the tubular body member.

175. The catheter of claim 174 wherein said catheter is advanced toward the tissue with a steerable sheath.

176. The catheter of claim 174 further comprising a coupler which connects the control shaft to the carrier assembly.

177. An ablation catheter, comprising:

an elongated, flexible, tubular body member having a proximal end, a distal end and a lumen extending therebetween;

a control shaft coaxially disposed and slidingly received within a lumen of the tubular body member;

a flexible carrier assembly, mechanically attached to the control shaft, said carrier assembly including multiple ablation elements used to deliver energy to tissue;

said ablation elements connected in series such that power is delivered to each ablation element sequentially.

178. The catheter of claim 177 comprising four or more ablation elements and further comprising less than five energy delivery wires extending from the proximal end of the tubular body member to the ablation elements.

179. The catheter of claim 177 further comprising a coupler which connects the control shaft to the carrier assembly.

180. An ablation catheter, comprising:

an elongated, flexible, tubular body member having a proximal end, a distal end and a lumen extending therebetween;

two or more control shafts coaxially disposed and slidingly received within the lumen of the tubular body member;

two or more flexible carrier assemblies each mechanically attached to a corresponding control shaft, each of said carrier assemblies including at least one ablation element used to deliver energy to tissue;

wherein retraction of each control shaft causes the connected carrier assembly to be constrained within the lumen of the tubular body member; and

wherein advancement of the each control shaft causes the corresponding carrier assembly to extend beyond the distal end of the tubular body member.

181. The catheter of claim 180 further comprising two or more connectors each of which connect each control shaft to a corresponding carrier assembly.

182. The catheter of claim 180 wherein each control shaft and corresponding carrier assembly can be completely retracted from the lumen of the tubular body member.

183. An ablation catheter, comprising:

an elongated, flexible, tubular body member having a proximal end, a distal end and a lumen extending therebetween;

a flexible control shaft coaxially disposed and slidingly received within the lumen of the Tubular Body Member, said control shaft including a proximal end, a distal end, and a mid-portion;

at least one ablation element mounted in the mid-portion of said control shaft

wherein the proximal end of the control shaft resides outside the proximal end of the tubular body member, the control shaft extending distally through the lumen of the control shaft such that the control shaft mid-portion resides outside the distal end of the tubular body member;

the control shaft then extending proximally such that the distal end of the control shaft resides outside the proximal end of the tubular body member.

wherein retraction of either the proximal and distal ends of the control shaft causes the mid-portion of the control shaft to be constrained within the lumen of the distal end of the tubular body member.

184. The catheter of claim 183 comprising multiple ablation elements.

185. The catheter of claim 184 wherein the multiple ablation elements reside in a linear pattern when the mid-portion of the control shaft is extended from the distal end of the tubular body member.

189. The catheter of claim 183 wherein retraction of both the proximal and distal ends of the control wire causes the mid-portion of the control shaft to be constrained within the lumen of the distal end of the tubular body member.

190. The catheter of claim 183 wherein advancement of the proximal and/or distal ends of the control wire causes the mid portion of the control shaft to transition from a constrained condition to an expanded condition as said mid-portion advances past the distal end of the tubular body member.

186-188. -188. (canceled)

191-254. -254. (canceled)