SHOCKWAVE CATHETER SYSTEM WITH ENERGY CONTROL

• US 20140074113A1
• Filed: 09/13/2012
• Published: 03/13/2014
• Est. Priority Date: 09/13/2012
• Status: Active Grant

• Current Assignee: Shockwave Medical, Incorporated
• Original Assignee: Shockwave Medical, Incorporated
• Inventors: Hakala, Doug, Adams, John M., Holmberg, Randy
• Granted Patent: US 9,333,000 B2
• Time in Patent Office: Days
• US Class Current: 606/128
• CPC Class Codes: A61B 17/22 Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for dilators A61M29/00
• CPC Class Codes: A61B 17/22022 using electric discharge
• CPC Class Codes: A61B 17/225 for extracorporeal shock wave lithotripsy [ESWL], e.g. by using ultrasonic waves
• CPC Class Codes: A61B 2017/00039 Electric or electromagnetic phenomena other than conductivity, e.g. capacity, inductivity, Hall effect
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00154 pulsed
• CPC Class Codes: A61B 2017/22025 applying a shock wave A61B2017/22091 takes precedence
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2017/22065 Functions of balloons dilating A61M29/02

Abstract

A system that breaks calcium in a liquid includes a catheter including first and second electrodes arranged to receive there-across a high electrical voltage at an initial low current. The high electrical voltage causes an electrical arc to form across the electrodes creating a gas bubble within the liquid, a high current to flow through the electrodes, and a mechanical shock wave. A power source provides the electrodes with the high electrical voltage at the initial current and terminates the high electrical voltage in response to the high current flow through the electrodes.

Claims

1. A system comprising:

a catheter including an elongated carrier, a balloon about the carrier in sealed relation thereto, the balloon being arranged to receive a fluid therein that inflates the balloon, and first and second electrodes within the balloon arranged to receive there-across a high electrical voltage at an initial low current, the high electrical voltage causing an electrical arc to form across the first and second electrodes within the balloon, the electrical arc creating a gas bubble within the liquid, a high current to flow through the first and second electrodes, and a mechanical shock wave within the balloon; and

a power source that provides the first and second electrodes with the high electrical voltage at the initial current and that terminates the high electrical voltage in response to the high current flow through the first and second electrodes.

2. The system of claim 1, wherein the power source includes a current sensor that senses current flowing through the first and second electrodes.

3. The system of claim 2, wherein the current sensor causes the power source to terminate the high electrical voltage when the current flowing through the first and second electrodes reaches a predetermined limit.

4. The system of claim 3, wherein the predetermined limit is on the order of fifty amperes.

5. The system of claim 1, further including a temperature sensor within the balloon that senses temperature of the fluid within the balloon, and wherein the power source is further responsive to the temperature sensor.

6. The system of claim 5, wherein the temperature sensor causes the power source to decrease energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing to control the temperature of the fluid.

7. The system of claim 6, wherein the temperature sensor causes the power source to decrease energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing to above two degrees Celsius above ambient temperature.

8. The system of claim 6, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses and wherein the temperature sensor causes the power source to decrease the energy applied to the first and second electrodes by temporarily terminating the serial electrical high voltage pulses.

9. The system of claim 6, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have a pulse rate, and wherein the temperature sensor causes the power source to decrease the energy applied to the first and second electrodes by decreasing the pulse rate of the serial electrical high voltage pulses.

10. The system of claim 1, wherein the balloon is a dilation balloon.

11. The system of claim 10, wherein the dilation balloon is an angioplasty balloon.

12. The system of claim 1, further comprising a timer that times a delay time in response to the high current flow through the first and second electrodes and wherein the power source terminates the high electrical voltage after the delay time is timed.

13. The system of claim 12, wherein the power source includes a current sensor that senses current flowing through the first and second electrodes and wherein the current sensor causes the timer to time the delay time when the current flowing through the first and second electrodes reaches a predetermined limit.

14. The system of claim 13, wherein the predetermined limit is on the order of fifty amperes.

15. A system comprising:

a catheter including an elongated carrier, the carrier having a guide wire lumen, a balloon having an inner surface about the carrier in sealed relation thereto, the balloon forming with the carrier, a channel arranged to receive a fluid that inflates the balloon, and first and second electrodes, within the balloon between the carrier and the inner surface of the balloon, arranged to receive there-across a high electrical voltage at an initial low current to cause an electrical arc to form across the first and second electrodes within the balloon, the electrical arc creating a gas bubble within the liquid, a high current to flow through the first and second electrodes, and a mechanical shock wave within the balloon; and

a power source that provides the first and second electrodes with the high electrical voltage at the initial current and that terminates the high electrical voltage in response to the high current flow through the first and second electrodes.

16. A system comprising:

a catheter including an elongated carrier, a balloon about the carrier in sealed relation thereto, the balloon being arranged to receive a fluid therein that inflates the balloon, and first and second electrodes within the balloon arranged to receive there-across a high electrical voltage at an initial low current to cause an electrical arc to form across the first and second electrodes within the balloon, the electrical arc creating a steam bubble within the liquid, a high current to flow through the first and second electrodes, and a mechanical shock wave within the balloon, the steam bubble increasing temperature of the fluid;

a temperature sensor within the balloon that senses temperature of the fluid within the balloon and

a power source that provides the first and second electrodes with the high electrical voltage at the initial current and that controls energy provided by the high electrical voltage in response to the sensed temperature of the fluid within the balloon.

17. The system of claim 16, wherein the temperature sensor causes the power source to decrease energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing to control the temperature of the fluid.

18. The system of claim 17, wherein the temperature sensor causes the power source to decrease energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing to about two degrees Celsius above ambient temperature.

19. The system of claim 17, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses, wherein each pulse of the serial electrical high voltage pulses has a pulse width, and wherein the temperature sensor causes the power source to decrease the energy applied to the first and second electrodes by decreasing the pulse width of the serial electrical high voltage pulses.

20. The system of claim 17, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses, wherein each pulse of the serial electrical high voltage pulses has an amplitude, and wherein the temperature sensor causes the power source to decrease the energy applied to the first and second electrodes by decreasing the amplitude of the serial electrical high voltage pulses.

21. The system of claim 17, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses and wherein the temperature sensor causes the power source to decrease the energy applied to the first and second electrodes by temporarily terminating the serial electrical high voltage pulses.

22. The system of claim 17, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have a pulse rate, and wherein the temperature sensor causes the power source to decrease the energy applied to the first and second electrodes by decreasing the pulse rate of the serial electrical high voltage pulses.

23. The system of claim 16, wherein the carrier has a guide wire lumen, wherein the balloon has an inner surface, wherein the balloon, with the carrier, forms a channel arranged to receive the fluid that inflates the balloon, and wherein the first and second electrodes are between the carrier and the inner surface of the balloon.

24. A method comprising:

providing a catheter including an elongated carrier, a balloon about the carrier in sealed relation thereto, the balloon being arranged to receive a fluid therein that inflates the balloon, and first and second electrodes within the balloon;

introducing the fluid into the balloon to inflate the balloon;

applying an electrical voltage across the first and second electrodes to form an electrical arc across the first and second electrodes;

sensing current flow through the first and second electrodes; and

varying the application of the electrical voltage across the first and second electrodes in response to sensed current flow through the first and second electrodes after the electrical arc is formed across the first and second electrodes.

25. The method of claim 24, wherein the varying step includes terminating the application of the electrical voltage across the first and second electrodes.

26. The method of claim 25, wherein the application of the high electrical voltage is terminated when the current flowing through the first and second electrodes reaches a predetermined limit.

27. The method of claim 26, wherein the predetermined limit is on the order of fifty amperes.

28. The method of claim 24, including the further step of sensing temperature of the fluid within the balloon, and wherein the varying step includes varying the application of the electrical voltage across the first and second electrodes in response to sensed temperature of the fluid.

29. The method of claim 28, wherein the varying step includes decreasing energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing to control the temperature of the fluid.

30. The method of claim 29, wherein the energy applied to the first and second electrodes is decreased responsive to the temperature of the fluid within the balloon increasing to above two degrees Celsius above ambient temperature.

31. The method of claim 28, wherein the applying step includes applying energy in the form of serial electrical high voltage pulses and wherein the varying step further includes decreasing the energy applied to the first and second electrodes by temporarily terminating the serial electrical high voltage pulses.

32. The method of claim 28, wherein the applying step includes applying energy in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have a pulse rate, and wherein the varying step further includes decreasing the energy applied to the first and second electrodes by decreasing the pulse rate of the serial electrical high voltage pulses.

33. The method of claim 24 including the further step of timing a delay time in response to sensed current flow through the first and second electrodes and wherein the varying step includes terminating the application of the electrical voltage across the first and second electrodes after timing the delay time.

34. The method of claim 33, wherein the delay time is timed when the current flowing through the first and second electrodes reaches a predetermined limit.

35. The method of claim 34, wherein the predetermined limit is on the order of fifty amperes.

36. A method comprising:

providing a catheter including an elongated carrier, a balloon about the carrier in sealed relation thereto, the balloon being arranged to receive a fluid therein that inflates the balloon, and first and second electrodes within the balloon;

introducing the fluid into the balloon to inflate the balloon;

applying energy in the form of an electrical voltage across the first and second electrodes to form an electrical arc across the first and second electrodes;

sensing temperature of the fluid within the balloon; and

varying the application of the energy across the first and second electrodes in response to sensed temperature of the fluid within the balloon.

37. The method of claim 36, wherein the varying step includes decreasing the energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing.

38. The method of claim 37, wherein the varying step includes decreasing the energy applied to the first and second electrodes responsive to the temperature of the fluid within the balloon increasing to about two degrees Celsius above ambient temperature.

39. The method of claim 38, wherein the applying step includes applying energy to the first and second electrodes in the form of serial electrical high voltage pulses, wherein each pulse of the serial electrical high voltage pulses has a pulse width, and wherein the varying step includes decreasing the energy applied to the first and second electrodes by decreasing the pulse width of the serial electrical high voltage pulses.

40. The method of claim 38, wherein the applying step includes applying energy to the first and second electrodes in the form of serial electrical high voltage pulses, wherein each pulse of the serial electrical high voltage pulses has an amplitude, and wherein the varying step includes decreasing the energy applied to the first and second electrodes by decreasing the amplitude of the serial electrical high voltage pulses.

41. The method of claim 36, wherein the applying step includes applying energy in the form of serial electrical high voltage pulses and wherein the varying step further includes decreasing the energy applied to the first and second electrodes by temporarily terminating the serial electrical high voltage pulses.

42. The method of claim 36, wherein the applying step includes applying energy in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have a pulse rate, and wherein the varying step further includes decreasing the energy applied to the first and second electrodes by decreasing the pulse rate of the serial electrical high voltage pulses.

43. A system that treats obstructions within bodily fluid comprising:

a catheter including first and second electrodes arranged to receive there-across a high electrical voltage at an initial low current, the high electrical voltage causing an electrical arc to form across the first and second electrodes within the bodily fluid, the electrical arc creating a gas bubble within the bodily fluid, a high current to flow through the first and second electrodes, and a mechanical shock wave within the bodily fluid; and

a power source that provides the first and second electrodes with the high electrical voltage at the initial current and that terminates the high electrical voltage in response to the high current flow through the first and second electrodes.

44. The system of claim 43, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have a pulse rate, and wherein the power source further controls the energy applied to the first and second electrodes by varying the pulse rate of the serial electrical high voltage pulses.

45. The system of claim 43, wherein the energy applied to the first and second electrodes by the power source is in the form of serial electrical high voltage pulses, wherein each pulse of the serial electrical high voltage pulses has an amplitude, and wherein the power source further controls the energy applied to the first and second electrodes by varying the amplitude of the serial electrical high voltage pulses.

46. The system of claim 43, further comprising a timer that times a delay time in response to the high current flow through the first and second electrodes and wherein the power source terminates the high electrical voltage after the delay time is timed.

47. The system of claim 46, wherein the power source includes a current sensor that senses current flowing through the first and second electrodes and wherein the current sensor causes the timer to time the delay time when the current flowing through the first and second electrodes reaches a predetermined limit.

48. The system of claim 47, wherein the predetermined limit is on the order of fifty amperes.

49. A method comprising:

providing a catheter including first and second electrodes within the balloon;

applying an electrical voltage across the first and second electrodes to form an electrical arc across the first and second electrodes;

sensing current flow through the first and second electrodes; and

varying the application of the electrical voltage across the first and second electrodes in response to sensed current flow through the first and second electrodes after the electrical arc is formed across the first and second electrodes.

50. The method of claim 49, wherein the applying step includes applying energy in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have a pulse rate, and wherein the varying step further includes controlling the energy applied to the first and second electrodes by varying the pulse rate of the serial electrical high voltage pulses.

51. The method of claim 49, wherein the applying step includes applying energy in the form of serial electrical high voltage pulses, wherein the serial electrical high voltage pulses have amplitudes, and wherein the varying step further includes controlling the energy applied to the first and second electrodes by varying the amplitudes of the serial electrical high voltage pulses.

52. The method of claim 49 including the further step of timing a delay time in response to sensed current flow through the first and second electrodes and wherein the varying step includes terminating the application of the electrical voltage across the first and second electrodes after timing the delay time.

53. The method of claim 52, wherein the delay time is timed when the current flowing through the first and second electrodes reaches a predetermined limit.

54. The method of claim 53, wherein the predetermined limit is on the order of fifty amperes.