Device for ablating body tissue

• US 7,942,871 B2
• Filed: 05/11/2007
• Issued: 05/17/2011
• Est. Priority Date: 05/12/2006
• Status: Active Grant

• Current Assignee: Auris Health, Inc. (Johnson & Johnson)
• Original Assignee: VytronUS, Inc. (Johnson & Johnson)
• Inventors: Arenson, James W., Thapliyal, Hira V., Gallup, David A.
• Primary Examiner(s): Johnson, III; Henry M
• Assistant Examiner(s): ROANE, AARON F
• Application Number:
  US11/747,867
• Publication Number:
  US 20070265610A1
• Time in Patent Office: 1,467 Days
• Field of Search: 606/27, 606/28, 606 41- 49
• US Class Current: 606/28
• CPC Class Codes: A61B 17/2202 the ultrasound transducer being inside patient's body at the distal end of the catheter
• CPC Class Codes: A61B 17/320068 using mechanical vibrations, e.g. ultrasonic A61B17/22012 takes precedence; dental tooth drilling devices operated by vibration A61C3/03; removing intra-ocular material using mechanical vibrations A61F9/00745
• 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 2017/00106 ultrasonic
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/22024 with a part reflecting mechanical vibrations, e.g. for focusing
• CPC Class Codes: A61B 2017/320069 for ablating tissue
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61N 2007/0078 with multiple treatment transducers
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: A61N 7/022 intracavitary

Abstract

A cardiac ablation system including an ablation catheter having an anchor adapted to support the ablation catheter within an atrium of a heart and an ultrasound emitter disposed radially outward from a rotation axis and from the anchor, and a control mechanism adapted to rotate the ultrasound emitter about the rotation axis and to provide ablation energy to the ultrasound emitter to ablate heart tissue.

Claims

1. A cardiac ablation system comprising:

a fluid source; and

an ablation catheter slidably disposed in an outer catheter, the ablation catheter comprising an anchor adapted to support the ablation catheter within an atrium of a heart and an ultrasound emitter disposed radially outward from a rotation axis and from the anchor, and a control mechanism adapted to rotate the ultrasound emitter about the rotation axis and to provide ablation energy to the ultrasound emitter to ablate heart tissue, wherein the ablation catheter is axially movable relative to the outer catheter thereby allowing control of lesion depth by adjustment of distance between the ultrasound emitter relative to the heart tissue, and wherein the ultrasound emitter comprises an ultrasound transducer coupled to a backing element, the ultrasound transducer being generally disc shaped, and wherein the backing element is adapted to reflect ultrasound energy from the ultrasound transducer towards a distal end of the ablation catheter, the ultrasound energy being directed distally from a distally facing surface of the disc, and wherein fluid from the fluid source exits a lumen of the ablation catheter and flows past the transducer to provide for cooling thereof, and wherein the fluid provides a barrier between the transducer and blood so as to prevent blood from coagulating on the transducer.

2. The system of claim 1 further comprising an ultrasound emitter support extending radially outward from the rotation axis and supporting the ultrasound emitter.

3. The system of claim 2 wherein a distal portion of the ablation catheter comprises the emitter support.

4. The system of claim 2 wherein the emitter is disposed to emit ultrasound energy through a distal end of the support.

5. The system of claim 2 wherein the control mechanism is adapted to bend the emitter support at a desired angle from the rotation axis.

6. The system of claim 5 wherein the desired angle is formed at a first location along the emitter support, the control mechanism being further adapted to bend the emitter support at a second location along the emitter support.

7. The system of claim 2 wherein the ultrasound emitter support comprises an electrode in electrical communication with the control mechanism and the anchor comprises an electrode in electrical communication with the control mechanism.

8. The system of claim 1 wherein the control mechanism is adapted to move the anchor within a left atrium.

9. The system of claim 1 wherein the anchor extends substantially along the rotation axis, the ablation catheter being adapted to rotate with respect to the anchor.

10. The system of claim 1 wherein the anchor extends along an axis other than the rotation axis.

11. The system of claim 1 further comprising a delivery sheath adapted to contain the ablation catheter, either the delivery sheath or the ablation catheter comprising a port through which the anchor extends.

12. The system of claim 1 further comprising a second anchor supporting the ablation catheter.

13. The system of claim 1 wherein the emitter is distally and proximally translatable with respect to the anchor.

14. The system of claim 13 wherein the emitter is supported by a transducer support extending radially outward from the rotation axis and is distally and proximally translatable with respect to the anchor.

15. The system of claim 1 wherein the anchor is adapted to contact a heart tissue surface.

16. The system of claim 15 wherein the anchor is adapted to contact an interior surface of a pulmonary vein.

17. The system of claim 1 further comprising a delivery sheath surrounding the ablation catheter, the anchor being expandable to contact a support catheter surrounding the ablation catheter.

18. The system of claim 1 wherein the system further comprises a fluid exit port adjacent to the transducer.

19. The system of claim 1 wherein the ultrasound emitter is disposed proximal to a distal end of the ablation catheter, the ablation catheter further comprising a fluid chamber in communication with the fluid source, disposed between the ultrasound emitter and the distal end of the catheter, and in fluid communication with the distal end of the catheter.

20. The system of claim 19 wherein the fluid chamber comprises a plurality of fluid exit channels formed in the distal end of the catheter.

21. The system of claim 1 further comprising a distance sensor adapted to sense distance between the ultrasound emitter and a tissue surface.

22. The system of claim 21 wherein the ultrasound emitter and the distance sensor comprise an ultrasound transducer.

23. The system of claim 1 further comprising an ablation depth sensor.

24. The system of claim 23 wherein the ultrasound emitter and ablation depth sensor comprise an ultrasound transducer.

25. A cardiac ablation system comprising:

a fluid source; and

an ablation catheter slidably disposed in an outer catheter, the ablation catheter comprising an ultrasound emitter and an ultrasound emitter support extending radially outward from a rotation axis and supporting the ultrasound emitter, and a control mechanism adapted to rotate the ultrasound emitter about the rotation axis and to provide ablation energy to the ultrasound emitter to ablate heart tissue and adapted to bend the emitter support at a desired angle from rotation axis, wherein the ablation catheter is axially movable relative to the outer catheter thereby allowing control of lesion depth by adjustment of distance between the ultrasound emitter relative to the heart tissue, and wherein the ultrasound emitter comprises an ultrasound transducer coupled to a backing element, the ultrasound transducer being generally disc shaped, and wherein the backing element is adapted to reflect ultrasound energy from the ultrasound transducer towards a distal end of the ablation catheter, the ultrasound energy being directed distally from a distally facing surface of the disc, and wherein fluid from the fluid source exits a lumen of the ablation catheter and flows past the transducer to provide for cooling thereof, and wherein the fluid provides a barrier between the transducer and blood so as to prevent blood from coagulating on the transducer.

26. The system of claim 25 wherein the desired angle is formed at a first location along the emitter support, the control mechanism being further adapted to bend the emitter support at a second location along the emitter support.

27. The system of claim 25 wherein the ultrasound emitter comprises an ultrasound transducer, the system further comprising a fluid source and a fluid flow path adjacent to the transducer.

28. The system of claim 27 wherein the system further comprises a fluid exit port adjacent to the transducer.

29. The system of claim 25 further comprising a distance sensor adapted to sense distance between the ultrasound emitter and a tissue surface.

30. The system of claim 29 wherein the ultrasound emitter and the distance sensor comprise an ultrasound transducer.

31. The system of claim 25 further comprising an ablation depth sensor.

32. The system of claim 31 wherein the ultrasound emitter and ablation depth sensor comprise an ultrasound transducer.