Catheter Systems for Cardiac Arrhythmia Ablation

• US 20120143177A1
• Filed: 12/07/2010
• Published: 06/07/2012
• Est. Priority Date: 12/07/2010
• Status: Active Grant

• Current Assignee: Boaz Avitall
• Original Assignee: Boaz Avitall
• Inventors: Avitall, Boaz
• Granted Patent: US 11,246,653 B2
• Time in Patent Office: Days
• US Class Current: 606/21
• 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 18/24 with a catheter A61B18/26, A61B18/28 take precedence
• CPC Class Codes: A61B 2018/00023 closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/0022 Balloons
• CPC Class Codes: A61B 2018/00351 Heart
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00369 Heart valves
• CPC Class Codes: A61B 2018/00375 Ostium, e.g. ostium of pulmonary vein or artery
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00815 measured by a thermistor
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure

Abstract

A plurality of catheter-based ablation apparatus embodiments are provided that address several areas of atrial target tissue and which feature firm and consistent ablation element to tissue contact enabling the creation of effective continuous lesions.

Claims

1. A device for ablating tissue in a body organ chamber, including heart chambers, comprising:

(a) a guide body sheath having a deflectable distal end portion;

(b) a guidewire extendable from said distal end portion of said guide body to form a guidewire loop that is controllable to create forced contact with organ chamber tissue;

(c) an inflatable ablation balloon device mounted on a flexible guide shaft able to travel over said guidewire; and

(d) a loop control element for controlling the size, shape and disposition of said guidewire loop.

2. A device for ablating tissue as in claim 1 further comprising balloon control element for advancing and retracting said balloon along said guidewire loop to allow for tissue contact and the creation of continuous lesions.

3. A device for ablating tissue as in claim 1 wherein said loop control element includes a pull wire.

5. A device for ablating tissue as in claim 1 wherein the surface of said ablation balloon device further comprises a plurality of thermistors and electrodes for temperature monitoring and real-time electrical activity assessment of lesion efficacy and maturation.

6. A device for ablating tissue as in claim 1 wherein said balloon device further comprises electrodes on the distal and proximal balloon margins for marking lesion and balloon location, electrical activity and trans-balloon impedance.

7. A device for ablating tissue as in claim 1 wherein said loop control element further comprises a mechanism for locking said guidewire loop.

8. A device for ablating tissue as in claim 1 wherein said balloon uses radio frequency to ablate tissue.

9. A device for ablating tissue as in claim 8 wherein said balloon includes a cooling mechanism.

10. A device for ablating tissue as in claim 9 wherein said cooling mechanism includes a system for circulating cooling liquid inside said balloon at a desired pressure.

11. A device for ablating tissue as in claim 8 wherein said balloon has an outer surface that comprises a plurality of segmented separated conductive ablation electrodes and is configured such that radio frequency power can be delivered selectively only to an electrode in contact with tissue.

12. A device for ablating tissue as in claim 11 further comprising a plurality of thermistors and recording electrodes on the surface of said balloon insulated from said ablation electrodes for monitoring temperature and real-time electrical activity assessment.

13. A device for ablating tissue as in claim 1 further comprising a control handle in a proximal portion of said guide body and containing devices for controlling said guidewire loop and said balloon device.

14. A device for ablating tissue as in claim 13 wherein said control handle further comprises an element for connecting the interior said balloon with a source of fluid selected from the group consisting of filling and recirculating materials including gases, liquefied gases, and liquid solutions.

15. A device for ablating tissue as in claim 13 wherein said control handle further comprises a reciprocating device connected to said guide shaft for controlling the position of said balloon device along said guidewire.

16. A device for ablating tissue as in claim 14 wherein said control handle further comprises a reciprocating device for controlling the position of said balloon device along said guidewire.

17. A device for ablating tissue as in claim 13 wherein said handle includes a guidewire locking mechanism.

18. A device for ablating tissue as in claim 16 wherein said handle includes a guidewire locking mechanism.

19. A device for ablating tissue as in claim 11 wherein said ablation electrodes are painted on the surface of said balloon.

20. A device for ablating tissue as in claim 12 wherein a thermistor and recording electrodes are associated with each ablation electrode balloon device is mounted on a flexible catheter shaft that rides over said guidewire.

21. A device for ablating tissue as in claim 1 wherein said balloon is a cryogenic device.

22. A device for ablating tissue as in claim 21 wherein said balloon device comprises an inner cryogenic balloon and an outer insulating balloon.

23. A device for ablating tissue as in claim 22 said balloon device further comprises ring electrodes flanking said balloon device.

24. A device for ablating tissue as in claim 21 wherein said balloon device further comprises a plurality of thermistors and recording electrodes distributed around the balloon circumference.

25. A device for ablating tissue as in claim 22 wherein said outer balloon device further comprises a plurality of thermistors and recording electrodes distributed around the balloon circumference.

26. A device for ablating tissue as in claim 21 wherein said balloon device is designed for use with a cryogenic fluid selected from the group consisting of liquid nitrous oxide (N₂O) and other suitable cryogenic fluids.

27. A device for ablating tissue as in claim 22 wherein said outer balloon is designed to be filled with an absorbable insulating gas.

28. A device for ablating tissue as in claim 22 wherein said outer balloon is provided with multiple circumferentially distributed separated recording elements made from highly conductive painted compound and thermistors to record pre/post ablation electrical activity and temperature to assess the tissue ablation efficiency.

57. A device for ablating tissue as in claim 5 wherein said balloon device further comprises electrodes on the distal and proximal balloon margins for marking lesion and balloon location, electrical activity and trans-balloon impedance.

58. A device as in claim 10 wherein said cooling liquid is saline.

59. A device as in claim 1 wherein said guidewire loop includes a relatively soft tip segment attached to the end of the sheath by means of a technique selected from a fixed attachment and a pull wire.

65. A device for ablating tissue as in claim 21 wherein said balloon catheter consists of a single inflatable balloon.

66. A device for ablating tissue as in claim 27 wherein said insulating gas includes nitrogen (N₂).

82. A device for ablating tissue as in claim 1 wherein said catheter guide shaft is approximately 7 F.

83. A device for ablating tissue as in claim 8 wherein the balloon measures about 30 mm long by 15 mm in diameter when fully inflated.

84. A device for ablating tissue as in claim 11 wherein the number of ablation electrodes is eight.

85. A device for ablating tissue as in claim 27, including means to regulate the pressure in the outer balloon to maintain expansion, yet allow displacement of the gas at a point of forced tissue contact.

4. A device for ablating tissue wherein said guide body further comprises an inflatable guide body balloon located at the distal portion thereof for preventing the guide body from retracting back through a penetrated chamber wall during a procedure.

64. A device for ablating tissue as in claim 4 further comprising a connected source for inflating and deflating said guide body balloon.

29. A device for ablating tissue in a cardiac chamber comprising:

(a) a guide body sheath having a deflectable distal end portion;

(b) a guidewire extendable from said distal end portion, said guidewire having a shaped distal anchoring section for anchoring said guidewire with respect to tissue to be ablated in a chamber;

(c) an inflatable ablation balloon device selected from radio frequency and cryogenic balloon devices able to travel over said guidewire in an inflated or deflated state; and

(d) a guidewire control element for controlling the extension of said guidewire.

30. A device for ablating tissue as in claim 29 wherein said distal anchoring section of said guidewire is designed to be placed in the left atrial appendage of a heart.

31. A device for ablating tissue as in claim 29 wherein said distal anchoring section of said guidewire is designed to be placed in a pulmonary vein for the creation of pulmonary vein isolation lesions, when inflated, said ablation balloon filling and occluding said pulmonary vein.

32. A device for ablating tissue as in claim 29 wherein said ablation balloon device is mounted on a flexible catheter guide shaft that rides over said guidewire.

33. A device for ablating tissue in a cardiac chamber comprising:

(a) a guide body sheath having a deflectable distal end portion;

(b) a pair of malleable but relatively rigid pre-shaped torquable support sheath elements extendable from said distal end of said guide body sheath; and

(c) a multi-electrode flexible recording/ablation catheter carried between and supported by said two support sheath elements such that the support sheath elements provide a stable anchor for applying said catheter exposed therebetween to tissue.

34. A device for ablating tissue as in claim 33 wherein said recording/ablation catheter further comprises a plurality of spaced recording and ablation electrode elements.

35. A device for ablating tissue as in claim 34 wherein the length and spacing of said ablation electrode elements enables the creation of continuous linear lesions.

36. A device for ablating tissue as in claim 35 wherein said spaced ablation elements are electrodes that comprise wound wire.

37. A device for ablating tissue as in claim 36 wherein said electrodes are approximately 5 mm in length and separated by approximately 2 mm.

38. A device for ablating tissue as in claim 34 further comprising thermistors placed between recording/ablation electrodes.

39. A device for ablating tissue as in claim 33 wherein said recording/ablation catheter is attached to one of said pair of pre-shaped torquable support sheath elements and is adjustable with respect to the other for adjusting the length of catheter exposed.

40. A device for ablating tissue as in claim 33 wherein said malleable but relatively rigid pre-shaped torquable support sheath elements are pre-shaped with respect to each other to allow insertion into spaced separate cardiac pulmonary veins or other spaced conduits.

41. A device for ablating tissue as in claim 40 wherein said pre-shaped support sheath elements are torquable to control and adjust ablation catheter positioning and tissue contact.

42. A device for ablating tissue as in claim 41 wherein said placement of said two support sheath elements enables said recording/ablation catheter to be firmly positioned against tissue for the creation and assessment of linear lesions.

43. A device for ablating tissue as in claim 39 further comprising a pull wire connected to one end of said multi-electrode flexible recording/ablation catheter for adjusting the exposed length thereof.

44. A device for ablating tissue as in claim 40 designed to ablate tissue between pulmonary vein orifices.

45. A device for ablating tissue as in claim 33 further comprising a locking device for locking the position of said pre-shaped support sheath elements with respect to said guide body.

46. A device for ablating tissue as in claim 33 further comprising a means for supplying electrical power to said ablation electrodes and receiving signals from said measuring devices to said catheter.

47. A device for ablating tissue as in claim 33 further comprising a control system for adjusting the relative positions and shapes of said guide body and said pair of support sheath elements and fixing said positions.

60. A device as in claim 33 wherein the length of said multi-electrode flexible recording/ablation catheter exposed between said support sheaths is adjustable.

61. A device as in claim 60 wherein the length and shape of said multi-electrode flexible recording/ablation catheter exposed is controlled by extending the catheter in and out of one or both of said support sheaths.

62. A device for ablating tissue as in claim 33 further comprising a control handle including extension and deflection controllers and means for locking the catheter and sheaths in place.

63. A device for ablating tissue as in claim 33 further comprising a control rod/wire for contacting said flexible recording/ablation catheter for aiding in the control of tissue contact, position and catheter shape.

48. A device for ablating tissue comprising:

(a) a guide body sheath having a deflectable distal end portion with an opening therein;

(b) a guiding and recording catheter extendable from said distal end portion of said guide body having a J-shaped-type loop distal end portion provided with a plurality of recording elements;

(c) an inflatable ablation balloon device designed to travel over said guiding and recording catheter device, said inflatable ablation balloon device being guided and stabilized by said guiding and recording catheter device; and

(d) a control element for controlling the extension of said guiding and recording catheter from said guide body sheath.

49. A device for ablating tissue as in claim 48 wherein said J-shaped loop of said guiding and recording catheter further comprises a loop portion designed to be inserted into a pulmonary vein orifice or other conduit, said loop portion further being equipped with a plurality of spaced recording and stimulation electrodes and thermistors for the assessment of lesion formation and efficacy post-ablation.

50. A device for ablating tissue as in claim 49 wherein said inflatable ablation balloon device further comprises a proximal ring electrode for determining lesion adequacy and maturation with said J-catheter loop electrodes.

51. A device for ablating tissue as in claim 50 wherein said inflatable ablation balloon device further comprises ring electrodes placed both distal and proximal to said balloon.

52. A device for ablating tissue as in claim 51 wherein when said ablation balloon is placed in the orifice of a pulmonary vein, pulmonary vein occlusion and ablation can be assessed by impedance measurements between said distal and proximal ring electrodes by applying a low-power, high-frequency energy that is transmitted therebetween.

53. A device for ablating tissue as in claim 48 wherein said ablation balloon device is connected to a balloon catheter shaft that travels over said guiding catheter.

54. A device for ablating tissue as in claim 48 wherein said ablation balloon device applies an ablation technique selected from radio frequency and cryogenics.

55. A device for ablating tissue as in claim 48 including a control element for adjusting the position of ablation balloon device along said guiding and recording catheter.

56. A device for ablating tissue as in claim 48 further comprising means for assessing phrenic nerve functions during ablation including an element for providing high intensity pulse electrical stimulation and an element for monitoring diaphragmatic movement.

67. A method of creating circumferential linear lesions by ablation in an organ chamber of interest comprising:

(a) providing a device for ablating tissue comprising;

1) a guide body sheath having a deflectable distal end portion;

2) a guidewire extendable from said distal end portion of said guide body to form a guidewire loop that is controllable to create forced contact with organ chamber tissue;

3) an inflatable ablation balloon device able to travel over said guidewire; and

4) a loop control element for controlling the size, shape and disposition of said guidewire loop;

(b) expanding and adjusting said guidewire loop in said organ chamber until it is tightly contacting the wall of said chamber; and

(c) inflating said balloon and tracking said balloon catheter along said guidewire loop incrementally while using said balloon to ablate tissue at a plurality of positions to create a circumferential lesion in said organ chamber.

68. A method as in claim 67 wherein said chamber is the left atrium of a heart.

69. A method as in claim 67 wherein said balloon catheter is selected from the group consisting of cryogenic and radio frequency ablation devices.

70. A method as in claim 67 wherein the surface of said balloon further comprises a plurality of thermistors and electrodes and wherein the method further comprises temperature and real-time electrical activity monitoring, assessment of lesion efficacy and maturation.

71. A method as in claim 69 wherein said balloon catheter is a cryogenic device having an inner cryogenic balloon and an outer insulating balloon with insulating medium therebetween and comprising exposing insulated surfaces of the balloon to the interior of said organ chamber while displacing said outer balloon at interfaces with tissue enabling cryogenic fluid to address tissue to be ablated through an uninsulated surface, the outer balloon gas pressure being maintained to be just above the pressure within the chamber.

72. A method as in claim 69 wherein said balloon catheter is a radio frequency ablation device and further comprising circulating a cooling fluid at constant pressure through said inflated balloon during the ablation of tissue.

79. A method as in claim 72 further comprising determining lesion maturation by monitoring and terminating the RF power based on a decrease in local electrogram amplitude and maximal frequency spectra of the local electrogram.

80. A method as in claim 72 including modulating the RF power output based on controlling the rate of temperature rise, dT/dt.

81. A method as in claim 69 wherein the balloon catheter is controlled such that radio frequency (RF) power or other energy source used for ablation is automatically adjusted to be delivered to the electrodes with firm contact with the tissues by means of the local electrogram response to ablation energy based on a parameter selected from local reduction of the amplitude of the electrical activity, frequency spectral changes or the rate of the temperature change or any combination thereof.

73. A method of ablating tissue to create isolation lesions at orifice interfaces between blood vessels and an organ chamber comprising:

(a) providing an ablation device comprising;

1) a guide body sheath having a deflectable distal end portion with an opening therein;

2) a guiding and recording catheter extendable from said distal end portion of said guide body sheath having a J-shaped-type loop distal end portion provided with a plurality of recording electrodes;

3) an inflatable ablation balloon device designed to travel over said guiding catheter device, said inflatable ablation balloon device being guided and stabilized by said guiding catheter; and

4) a control element for controlling the extension of said guiding and recording catheter from said guide body;

(b) extending said guiding and recording catheter and steering it into the orifice of a blood vessel of interest;

(c) causing said ablation balloon to travel over said guiding and recording catheter until it is situated in the orifice of said vessel of interest;

(d) using said ablation balloon to ablate tissue at the orifice of said vessel of interest; and

(e) recording the local electrogram to determine the efficacy and maturation of the ablation.

74. A method as in claim 73 wherein said ablation balloon is a cryogenic device and including measuring the trans-balloon impedance during said ablation procedure to monitor vessel occlusion and lesion efficacy.

75. A method as in claim 73 wherein said vessel is a pulmonary vein and further comprising assessing phrenic nerve function during ablation.

76. A method of ablating tissue and creating linear lesions between orifices of a plurality of vessels interfacing an organ chamber comprising:

(a) providing a device for ablating tissue comprising;

1) a guide body sheath having a deflectable distal end portion;

2) a pair of malleable but relatively rigid pre-shaped torquable support sheath elements extendable from said distal end of said guide body; and

3) a multi-electrode flexible recording/ablation catheter carried between and supported by said two extendable support sheath elements such that the support sheath elements can provide a stable anchor for said catheter exposed therebetween;

(b) adjusting said torquable support sheath elements and inserting them into a pair of vessel orifices, the multi-electrode flexible recording/ablation catheter being pressed against the tissue therebetween; and

(c) using said recording/ablation catheter to create a lesion between said orifices.

77. A method as in claim 76 including adjusting the length of said recording/ablation catheter as required.

78. A method as in claim 76 further comprising adjusting said recording/ablation catheter using an extendable control rod.