Apparatus for procedures related to the electrophysiology of the heart

• US 5,755,663 A
• Filed: 06/20/1996
• Issued: 05/26/1998
• Est. Priority Date: 08/19/1994
• Status: Expired due to Fees

• Current Assignee: Novoste Corporation (Novt Corporation)
• Original Assignee: Novoste Corporation (Novt Corporation)
• Inventors: Johnson, Cheryl R., Larsen, Charles E., Trip, Roelof
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US08/670,177
• Time in Patent Office: 705 Days
• Field of Search: 606/20, 606/21, 606/28, 606/29, 606/41, 606/33, 128/642, 607/99-102, 607/113, 607/122, 600/374
• US Class Current: 600/374
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• 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 2017/00243 cardiac
• CPC Class Codes: A61B 2018/00047 using Peltier effect
• CPC Class Codes: A61B 2018/0212 using an instrument inserted into a body lumen, e.g. catheter
• CPC Class Codes: A61B 2018/0237 with a thermoelectric element in the probe for cooling purposes
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: H10N 10/00 Thermoelectric devices comprising a junction of dissimilar materials, i.e. devices exhibiting Seebeck or Peltier effects integrated devices or assemblies of multiple devices H10N19/00

Abstract

Methods and apparatus are disclosed for use in procedures related to ther electrophysiology of the heart, such as identifying or evaluating the electrical activity of the heart, diagnosing and/or treating conditions associated with the electrophysiology of the heart. An apparatus having thermocouple elements of different electromotive potential conductively connected at a junction is introduced into the interior of the heart and a section of heart tissue is contacted with the junction. An electrical current is passed through the thermocouple elements to reduce the temperature of the junction in accordance with the Peltier effect and thereby cool the contacted heart tissue. The effect of the cooling may be monitored and, if desired, the section of heart tissue may be treated.

Claims

1. Apparatus for use in cardiac procedures, said apparatus including an elongated body with a proximal end portion and a distal end portion, said distal end portion comprising:

at least two electrodes comprising a first electrode and a second electrode proximally spaced from said first electrode;

at least one pair of thermocouple elements located between said electrodes, each of said thermocouple elements having a first end and a second end;

said thermocouple elements being conductively connected at said first ends at a junction, whereby application of a voltage across said thermocouple elements affects the temperature of said junction in accordance with the Peltier effect.

2. The apparatus of claim 1 wherein one of said thermocouple elements is proximally located relative to said other thermocouple element.

3. The apparatus of claim 1 further comprising at least a second pair of thermocouple elements located between said electrodes;

said second pair of thermocouple elements being conductively connected at a second function, said second junction being conductively connected to said one pair of thermocouple elements.

4. The apparatus of claim 1 further comprising means for monitoring the temperature of said junction.

5. Apparatus of claim 4 wherein said means for monitoring the temperature of said junction is embedded in said junction.

6. The apparatus of claim 1, wherein said first electrode comprises said junction.

7. The apparatus of claim 1 further comprising a fixture for supporting said thermocouple elements within said distal end portion.

8. The apparatus of claim 1 wherein said junction comprises a thermoconductive solder.

9. Apparatus of claim 1 further comprising a steering wire having a proximal end and a distal end and extending through said elongated body, wherein said proximal end of said steering wire is connected to a slidable hub located at said proximal end portion of said elongated body and said distal end of said steering wire is connected to said distal end portion of said elongated body.

10. Apparatus of claim 1 wherein said thermocouple elements are disposed in a parallel arrangement.

11. Apparatus of claim 10 wherein said first electrode comprises said junction.

12. Apparatus of claim 1 wherein said first electrode comprises a cap of an electrically conductive material and said cap is positioned at the distal tip of said distal end portion of said elongated body.

13. Apparatus of claim 3 wherein said second junction is proximal to and in alignment with said one pair of thermocouple elements.

14. Apparatus of claim 13 further comprising a third pair of thermocouple elements located between said electrodes, said third pair of thermocouple elements being conductively connected at a third junction, said third junction being conductively connected to said one pair of thermocouple elements.

15. Apparatus of claim 14 wherein said third junction is proximal to said one pair of thermocouple elements and adjacent to said second junction.

16. Apparatus of claim 1 comprising an electrical power supply conductively connected to said second ends of said thermocouple elements.

17. Apparatus of claim 16 wherein said power supply generates radiofrequency energy.

18. Apparatus of claim 17 wherein said power supply is connected to said distal electrode.

19. Apparatus of claim 16 wherein said power supply generates microwave frequency energy.

20. Apparatus of claim 19 wherein said power supply is connected to said distal electrode.

21. Apparatus of claim 16 wherein said power supply comprises a control for controlling and adjusting the temperature of said junction by controlling the applied voltage.

22. Apparatus of claim 16 further comprising a separate power supply capable of generating radiofrequency energy and conductively connected to a part of said distal end portion.

23. Apparatus of claim 16 further comprising a separate power supply capable of generating microwave frequency energy and conductively connected to a part of said distal end portion.

24. Apparatus of claim 1 comprising an electrical activity monitor conductively connected to said electrodes.

28. Apparatus of claim 21 wherein said electrode defines said junction.

25. Apparatus for use in cardiac procedures, said apparatus including an elongated body with a proximal end portion and a distal end portion, said distal end portion comprising:

at least two thermocouple elements conductively connected, whereby application of a voltage across said thermocouple elements affects the temperature of at least a part of said distal end portion in accordance with the Peltier effect; and

at least one electrode in proximity to said thermocouple elements.

26. Apparatus of claim 25 wherein said thermocouple elements are conductively connected to said electrode.

27. Apparatus of claim 26 wherein said thermocouple elements are conductively connected at a junction.

29. Apparatus of claim 25 comprising a second electrode proximal to said thermocouple elements.

30. Apparatus of claim 29 wherein said thermocouple elements are located between said electrodes.

31. Apparatus of claim 25 further comprising a carrier of low thermal and electrical conductivity wherein said thermocouple elements are mounted on said carrier.

32. Apparatus of claim 31 wherein said carrier is made of a material comprising a polyether ether ketone.

33. Apparatus of claim 31 wherein said carrier comprises a bore providing a conduit for introducing wires from the outside of said carrier to at least said thermocouple elements.

34. Apparatus of claim 31 comprising a thermoconductive epoxy applied between said thermocouple elements and at least a portion of the carrier.

35. Apparatus of claim 31 wherein said thermocouple elements are mounted in an axially extending end to end arrangement, said ends of said thermocouple elements being conductively connected at a junction.

36. Apparatus of claim 31 wherein said carrier comprises a bore providing a conduit for introducing wires from the outside of said carrier to at least said thermocouple elements and said electrodes.

37. Apparatus of claim 31 wherein said thermocouple elements are separated along their lengths when mounted on said carrier.

38. Apparatus of claim 25 further comprising a radio frequency energy conductor extending along said body between said proximal and distal end portions and in electrical communication with a selected part of said distal end portion.

39. Apparatus of claim 25 wherein said thermocouple elements are conductively connected at a junction.

40. Apparatus of claim 39 wherein said thermocouple elements are conductively connected to said electrode.

41. Apparatus of claim 40 wherein said electrode defines said junction.

42. Apparatus of claim 39 comprising a second electrode proximal to said thermocouple elements.

43. Apparatus of claim 42 wherein said thermocouple elements are located between said electrodes.

44. Apparatus of claim 42 wherein said junction is spaced from and in between said electrodes.

45. Apparatus of claim 44 wherein one of said thermocouple elements is proximal to said other thermocouple element.

46. Apparatus of claim 25 wherein said thermocouple elements have differing electromotive potentials.

47. Apparatus of claim 46 wherein said thermocouple elements are made of alloys comprising Bismuth-Telluride.

48. Apparatus for diagnosing and treating electrophysiological conditions of the heart, said apparatus including an elongated body with a proximal end portion and a distal end portion, said distal end portion comprising:

at least two electrodes comprising a first electrode and a second electrode proximally spaced from said first electrode;

an electrical activity monitor connected to said electrodes;

at least one pair of thermocouple elements located between said electrodes, each of said thermocouple elements having a first end and a second end;

said thermocouple elements being conductively connected at said first ends at a junction, whereby application of a voltage and induction of a current across said thermocouple elements affects the temperature of said junction in accordance with the Peltier effect; and

an electrical power supply connected to said second ends of said thermocouple elements.