US5542928A
Expired / Lapsed
US
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Method and device for thermal ablation having improved heat transfer
Assignee: Covidien LP
•
Filing: 1994-06-27
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Granted: 1996-08-06
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Expires: 2014-06-27
Abstract
Abstract A thermal ablation catheter includes an elongate body member having a heating element disposed over a predetermined length of its distal end or within an axial lumen. The heating element is suspended away from an exterior surface of the elongate member to form a circulation region thereunder. Alternatively, the heating element is distributed over some or all of the axial lumen. Thermally conductive fluid can be introduced through the lumen in the elongate member and into the circulation region to effect heat transfer. The catheter is used to introduce the thermally conductive medium to a hollow body organ where the heating element raises the temperature of the medium sufficiently to induce injury to the lining of the organ. Optionally, an expandable cage in the catheter or on an associated introducer sheath may be used in combination with a thermal ablation catheter. The expandable cage helps center the heating element on the catheter within the body organ and prevents direct contact between the heating element and the wall of the organ. When disposed on the catheter, the cage can be useful to position a flow directing element attached to the flow delivery lumen of the catheter. Heat transfer and temperature uniformity can be enhanced by inducing an oscillatory flow of the heat transfer medium through the catheter while heat is being applied.
Inventors
- 👤 Michael A. Evans
- 👤 Colin J. Nichols
- 👤 Laura Kemp
- 👤 William R. Dubrul
- 👤 Robert S. Behl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:23
CPC Classifications
A; A61; A61B; A61B18/00; A61B18/04; A61B18/08; A61B18/082; A61B17/00; A61B2017/00017; A61B2017/00022; A61B2017/00084; A61B2017/00092; A61B17/00234; A61B2017/00292; A61B17/22; A61B2017/22038; A61B17/42; A61B2017/4216; A61B2018/00053; A61B2018/00059; A61B2018/00089; A61B2018/00095; A61B2018/00315; A61B2018/00345; A61B2018/00404; A61B2018/00422; A61B2018/044; A61B2018/046; A61B90/00; A61B90/39; A61B2090/3933; A61B2218/00; A61B2218/001; A61B2218/002; A61F; A61F7/00; A61F2007/0059; A61F7/12; A61M; A61M1/00; A61M1/84; A61M1/85
Claims Analysis
Total Claims: 84
Claim 1
Independent Claim
93 words
A fluid mixing and heating catheter, said catheter comprising: an elongate member having a proximal end, a distal end, and a lumen extending therebetween; a heating element disposed within at least a portion of the length of the lumen so that fluid flowing through the lumen will contact the heating element; a fluid connector at the proximal end of the elongate member which connects the lumen to an external fluid source; and a power connector at the proximal end of the elongate member which connects the heating element to an external power source.
Claim 2
Dependent Claim
93 words
A fluid mixing and heating catheter, said catheter comprising: an elongate member having a proximal end, a distal end, and a lumen extending therebetween; a heating element disposed within at least a portion of the length of the lumen so that fluid flowing through the lumen will contact the heating element; a fluid connector at the proximal end of the elongate member which connects the lumen to an external fluid source; and a power connector at the proximal end of the elongate member which connects the heating element to an external power source.
Claim 3
Dependent Claim
43 words
A fluid mixing and heating catheter as in claim 1, wherein the elongate member is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 4
Dependent Claim
26 words
A fluid mixing and heating catheter as in claim 2, wherein the heating element is disposed within at least the distal-most 1 cm of the lumen.
Claim 5
Dependent Claim
18 words
A fluid mixing and heating catheter as in claim 1, wherein the heating element is a wire coil.
Claim 6
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 1, further comprising a layer of thermal insulation over at least a portion of an outside surface of the elongate member.
Claim 7
Dependent Claim
31 words
A fluid mixing and heating catheter as in claim 1, further comprising a fixture at the proximal end of the elongate member, which fixture comprises the fluid connector and power connector.
Claim 8
Dependent Claim
27 words
A fluid mixing and heating catheter as in claim 1, further comprising a flow directing element at the distal end of the lumen in the elongate member.
Claim 9
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 7, wherein the flow directing element has at least two ports for directing fluid flow in at least two different directions.
Claim 10
Dependent Claim
31 words
A fluid mixing and heating catheter as in claim 8, wherein at least two ports are directed to create a flow which diverges at an angle of about 60° to 150°.
Claim 11
Dependent Claim
22 words
A fluid mixing and heating catheter as in claim 1, further comprising a cage structure at the distal end of elongate member.
Claim 12
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 10, wherein the cage structure is expansible from a collapsed configuration to an expanded configuration which defines a heating volume therein.
Claim 13
Dependent Claim
35 words
A fluid mixing and heating catheter as in claim 11, wherein the cage structure is resilient so that it assumes the collapsed configuration when constrained and reassumes the expanded configuration when released from being constrained.
Claim 14
Dependent Claim
22 words
A fluid mixing and heating catheter as in claim 10, further comprising at least one temperature sensing element on the cage structure.
Claim 15
Dependent Claim
53 words
A fluid mixing and heating catheter as in claim 13, wherein the temperature sensing element comprises a penetrating member having a temperature transducer at a distal end thereof, where the penetrating member is disposed on the expansible cage, so that it will penetrate tissue adjacent to the cage when said cage is expanded.
Claim 16
Dependent Claim
23 words
A fluid mixing and heating catheter as in claim 14, wherein the penetrating member has a length of at least about 1 mm.
Claim 17
Dependent Claim
53 words
A system for mixing and heating a thermally conductive fluid within a hollow body organ, said system comprising; a fluid mixing and heating catheter as in claim 1; a power supply which connects to the power connector or the catheter; and an oscillatory pump which connects to the fluid connector on the catheter.
Claim 18
Dependent Claim
39 words
A system as in claim 16, wherein the elongate member is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 19
Dependent Claim
22 words
A system as in claim 17, wherein the heating element is disposed within at least the distal-most 1 cm of the lumen.
Claim 20
Dependent Claim
14 words
A system as in claim 16, wherein the heating element is a wire coil.
Claim 21
Dependent Claim
26 words
A system as in claim 16, further comprising a layer of thermal insulation over at least a portion of an outside surface of the elongate member.
Claim 22
Dependent Claim
27 words
A system as in claim 16, further comprising a fixture at the proximal end of the elongate member, which fixture comprises the fluid connector and power connector.
Claim 23
Dependent Claim
23 words
A system as in claim 16, further comprising a flow directing element at the distal end of the lumen in the elongate member.
Claim 24
Dependent Claim
26 words
A system as in claim 22, wherein the flow directing element has at least two ports for directing fluid flow in at least two different directions.
Claim 25
Dependent Claim
27 words
A system as in claim 23, wherein at least two ports are directed to create a flow which diverges at an angle of about 30° to 180°.
Claim 26
Dependent Claim
18 words
A system as in claim 16, further comprising a cage structure at the distal end of elongate member.
Claim 27
Dependent Claim
26 words
A system as in claim 25, wherein the cage structure is expansible from a collapsed configuration to an expanded configuration which defines a heating volume therein.
Claim 28
Dependent Claim
31 words
A system as in claim 26, wherein the cage structure is resilient so that it assumes the collapsed configuration when constrained and reassumes the expanded configuration when released from being constrained.
Claim 29
Dependent Claim
33 words
A system as in claim 25, further comprising at least one temperature sensing element on the cage structure and a temperature controller which modulates power delivery from the power supply to the catheter.
Claim 30
Independent Claim
58 words
A system as in claims 28, wherein the temperature sensing element comprises a penetrating member having a temperature transducer at a distal end thereof, wherein the penetrating member has a length of at least 1 mm and is disposed on the expansible cage, so that it will penetrate tissue adjacent to the cage when said cage is expanded.
Claim 31
Dependent Claim
17 words
A system as in claim 29, wherein the oscillatory pump is connected to an open fluid reservoir.
Claim 32
Dependent Claim
57 words
A fluid mixing and heating catheter comprising; an elongate member having a proximal end, a distal end, and a lumen extending therebetween; a heating element disposed within the lumen so that fluid flowing through the lumen will contact the heating element; and a flow directing element at the distal end of the lumen in the elongate member.
Claim 33
Dependent Claim
57 words
A fluid mixing and heating catheter comprising; an elongate member having a proximal end, a distal end, and a lumen extending therebetween; a heating element disposed within the lumen so that fluid flowing through the lumen will contact the heating element; and a flow directing element at the distal end of the lumen in the elongate member.
Claim 34
Dependent Claim
43 words
A fluid mixing and heating catheter as in claim 31, wherein the elongate member is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 35
Dependent Claim
26 words
A fluid mixing and heating catheter as in claim 31, wherein the heating element is distributed over at least the distal-most 1 cm of the lumen.
Claim 36
Dependent Claim
18 words
A fluid mixing and heating catheter as in claim 33, wherein the heating element is a wire coil.
Claim 37
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 31, further comprising a layer of thermal insulation over at least a portion of an outside surface of the elongate member.
Claim 38
Dependent Claim
36 words
A fluid mixing and heating catheter as in claim 31, further comprising a fixture at the proximal end of the elongate member, which fixture comprises a fluid connector, a power connector, and a temperature sensor connector.
Claim 39
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 31, wherein the flow directing element has at least two ports for directing fluid flow in at least two different directions.
Claim 40
Dependent Claim
31 words
A fluid mixing and heating catheter as in claim 37, wherein at least two ports are directed to create a flow which diverges at an angle of about 60° to 150°.
Claim 41
Dependent Claim
28 words
A fluid mixing and heating catheter as in claim 31, further comprising a cage structure at the distal end of elongate member disposed over the flow directory element.
Claim 42
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 39, wherein the cage structure is expansible from a collapsed configuration to an expanded configuration which defines a heating volume therein.
Claim 43
Dependent Claim
35 words
A fluid mixing and heating catheter as in claim 40, wherein the cage structure is resilient so that it assumes the collapsed configuration when constrained and reassumes the expanded configuration when released from being constrained.
Claim 44
Dependent Claim
22 words
A fluid mixing and heating catheter as in claim 39, further comprising at least one temperature sensing element on the cage structure.
Claim 45
Dependent Claim
53 words
A fluid mixing and heating catheter as in claims 42, wherein the temperature sensing element comprises a penetrating member having a temperature transducer at a distal end thereof, where the penetrating member is disposed on the expansible cage, so that it will penetrate tissue adjacent to the cage when said cage is expanded.
Claim 46
Dependent Claim
23 words
A fluid mixing and heating catheter as in claim 43, wherein the penetrating member has a length of at least about 1 mm.
Claim 47
Dependent Claim
53 words
A system for mixing and heating a thermally conductive fluid within a hollow body organ, said system comprising; a fluid mixing and heating catheter as in claim 16; a power supply which connects to the heating element on the catheter; and an oscillatory pump which connects to the lumen in the elongate member.
Claim 48
Dependent Claim
39 words
A system as in claim 45, wherein the elongate member is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 49
Dependent Claim
22 words
A system as in claim 45, wherein the heating element is disposed within at least the distal-most 1 cm of the lumen.
Claim 50
Dependent Claim
14 words
A system as in claim 47, wherein the heating element is a wire coil.
Claim 51
Dependent Claim
26 words
A system as in claim 46, further comprising a layer of thermal insulation over at least a portion of an outside surface of the elongate member.
Claim 52
Dependent Claim
32 words
A fluid mixing and heating catheter as in claim 45, further comprising a fixture at the proximal end of the elongate member, which fixture comprises the fluid connector and a power connector.
Claim 53
Dependent Claim
26 words
A system as in claim 45, wherein the flow directing element has at least two ports for directing fluid flow in at least two different directions.
Claim 54
Dependent Claim
27 words
A system as in claim 51, wherein at least two ports are directed to create a flow which diverges at an angle of about 60° to 150°.
Claim 55
Dependent Claim
24 words
A system as in claim 45, further comprising a cage structure at the distal end of elongate member dispose over the flow directing element.
Claim 56
Dependent Claim
26 words
A system as in claim 53, wherein the cage structure, is expansible from a collapsed configuration to an expanded configuration which defines a heating volume therein.
Claim 57
Dependent Claim
31 words
A system as in claim 54, wherein the cage structure is resilient so that it assumes the collapsed configuration when constrained and reassumes the expanded configuration when released from being constrained.
Claim 58
Dependent Claim
18 words
A system as in claim 53, further comprising at least one temperature sensing element on the cage structure.
Claim 59
Dependent Claim
49 words
A system as in claim 56, wherein the temperature sensing element comprises a penetrating member having a temperature transducer at a distal end thereof, where the penetrating member is disposed on the expansible cage, so that it will penetrate tissue adjacent to the cage when said cage is expanded.
Claim 60
Dependent Claim
19 words
A system as in claim 57, wherein the penetrating member has a length of at least about 1 mm.
Claim 61
Dependent Claim
53 words
An improved fluid mixing and heating catheter of the type including an elongate body having a proximal end, a distal end, and a lumen therebetween, and a heating element, wherein the improvement comprises locating the heating element within the lumen so that fluid will contact the heating element when passing through the lumen.
Claim 62
Dependent Claim
53 words
An improved fluid mixing and heating catheter of the type including an elongate body having a proximal end, a distal end, and a lumen therebetween, and a heating element, wherein the improvement comprises locating the heating element within the lumen so that fluid will contact the heating element when passing through the lumen.
Claim 63
Dependent Claim
43 words
An improved mixing and heating catheter as in claim 59, wherein the elongate body is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 64
Dependent Claim
27 words
An improved fluid mixing and heating catheter as in claim 60, wherein the heating element is disposed within at least the distal-most 1 cm of the lumen.
Claim 65
Dependent Claim
19 words
An improved fluid mixing and heating catheter as in claim 61, wherein the heating element is a wire coil.
Claim 66
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 60, further comprising a layer of thermal insulation over at least a portion of an outside surface of the elongate body.
Claim 67
Dependent Claim
31 words
An improved fluid mixing and heating catheter as in claim 59, wherein the improvement further comprises a flow directing element at the distal end of the lumen in the elongate member.
Claim 68
Dependent Claim
32 words
An improved fluid mixing and heating catheter as in claim 64, wherein the improvement further comprises a cage structure at the distal end of elongate member formed over the flow directing element.
Claim 69
Dependent Claim
53 words
An improved fluid heating and mixing catheter of the type including an elongate body having a proximal end, a distal end, and a lumen therebetween, and a heating element, wherein the improvement comprises a flow directing element at the distal end of the lumen and a cage structure surrounding the flow directing element.
Claim 70
Dependent Claim
53 words
An improved fluid heating and mixing catheter of the type including an elongate body having a proximal end, a distal end, and a lumen therebetween, and a heating element, wherein the improvement comprises a flow directing element at the distal end of the lumen and a cage structure surrounding the flow directing element.
Claim 71
Dependent Claim
44 words
An improved fluid mixing and heating catheter as in claim 59, wherein the elongate body is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 72
Dependent Claim
30 words
A improved fluid mixing and heating catheter as in claim 67, wherein a heating element disposed the improvement further comprises within at least the distal-most 1 cm of the lumen.
Claim 73
Dependent Claim
31 words
An improved fluid mixing and heating catheter as in claim 66, wherein the flow directing element has at least two ports for directing fluid flow in at least two different directions.
Claim 74
Dependent Claim
32 words
An improved fluid mixing and heating catheter as in claim 69, wherein at least two ports are directed to create a flow which diverges at an angle of about 60° to 150°.
Claim 75
Dependent Claim
32 words
An improved fluid mixing and heating catheter as in claim 70, wherein the improvement further comprises a cage structure at the distal end of elongate member disposed over the flow directing element.
Claim 76
Dependent Claim
71 words
An improved fluid heating and mixing catheter of the type including an elongate body having a proximal end, a distal end, and a lumen therebetween, a heating element, and a cage structure disposed over the distal end of the elongate body, wherein the improvement comprises at least one temperature sensor disposed on the cage structure to contact an inner surface of a hollow body organ when the cage is located therein.
Claim 77
Dependent Claim
71 words
An improved fluid heating and mixing catheter of the type including an elongate body having a proximal end, a distal end, and a lumen therebetween, a heating element, and a cage structure disposed over the distal end of the elongate body, wherein the improvement comprises at least one temperature sensor disposed on the cage structure to contact an inner surface of a hollow body organ when the cage is located therein.
Claim 78
Dependent Claim
44 words
An improved fluid mixing and heating catheter as in claim 72, wherein the elongate body is a flexible tube having a length in the range from 10 cm to 100 cm and a lumen diameter in the range from 2 mm to 10 mm.
Claim 79
Dependent Claim
29 words
A fluid mixing and heating catheter as in claim 73, wherein the improvement further comprises a heating element disposed within at least the distal-most 1 cm of the lumen.
Claim 80
Dependent Claim
30 words
A fluid mixing and heating catheter as in claim 72, wherein the improvement further comprises a flow directing element at the distal end of the lumen in the elongate member.
Claim 81
Dependent Claim
31 words
An improved fluid mixing and heating catheter as in claim 72, wherein the cage structure is expansible from a collapsed configuration to an expanded configuration which defines a heating volume therein.
Claim 82
Dependent Claim
36 words
An improved fluid mixing and heating catheter as in claim 76, wherein the cage structure is resilient so that it assumes the collapsed configuration when constrained and reassumes the expanded configuration when released from being constrained.
Claim 83
Dependent Claim
53 words
An improved fluid mixing and heating catheter as in claim 72, wherein the temperature sensing element comprises a penetrating member having a temperature transducer at a distal end thereof, where the penetrating member is disposed on the expandable cage, so that it will penetrate tissue adjacent the cage when said cage is expanded.
Claim 84
Dependent Claim
24 words
An improved fluid mixing and heating catheter as in claim 78, wherein the penetrating member has a length of at least about 1 mm.
References Cited (Backward Citations)
US4160455A
Cited
US4676258A
Cited
US4709698A
Cited
US4955377A
Cited
US5084044A
Cited
US5045056A
Cited
US5100388A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-08-06 | 2000-02-05 | 2000-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-08-06 | 2004-02-05 | 2004-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-08-06 | 2008-02-05 | 2008-08-06 | $7700.00 | Window Closed / Lapsed |