Shockwave catheter system with energy control

• US 8,728,091 B2
• Filed: 11/13/2013
• Issued: 05/20/2014
• 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
• Primary Examiner(s): TYSON, MELANIE RUANO
• Application Number:
  US14/079,463
• Publication Number:
  US 20140074111A1
• Time in Patent Office: 188 Days
• Field of Search: 606/127, 606/128
• 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 balloon catheter for delivering shockwaves to a calcified lesion comprising:

an elongated carrier;

a flexible balloon mounted on the elongate carrier, said balloon being fillable with a conductive fluid;

a pair of electrodes on the elongated carrier within the balloon; and

a power source coupled to the electrodes for supplying voltage pulses to the electrodes, each voltage pulse generating an arc in the fluid within the balloon and causing current to flow between the electrodes and producing a shockwave;

wherein the power source includes a current sensor for detecting the current flow between the electrodes during each voltage pulse, and wherein when the current reaches a predetermined value during each voltage pulse, the sensor generates a signal that causes the power source to terminate the voltage supplied to the electrodes for that pulse.

2. The balloon catheter of claim 1, wherein the predetermined value is 50 amps.

3. The balloon catheter of claim 1, wherein the carrier has a guidewire lumen.

4. The balloon catheter of claim 1, wherein the power source further includes a delay timer with a predetermined delay time, the delay timer being triggered in response to the sensor signal and wherein the voltage supplied to the electrodes is terminated after the predetermined delay time has expired.

5. The balloon catheter of claim 4, wherein the predetermined delay time is 100 nanoseconds or more.

6. A balloon catheter for delivering shockwaves to a calcified lesion comprising:

an elongated carrier;

a flexible balloon mounted on the elongate carrier, said balloon being fillable with a conductive fluid;

a pair of electrodes on the elongated carrier within the balloon; and

a power source coupled to the electrodes for supplying voltage pulses to the electrodes, each voltage pulse generating an arc in the balloon producing a shockwave, wherein the power source includes a current sensor configured to detect current flow between the electrodes during each pulse;

wherein the power source is configured to terminate the voltage supply a predetermined delay time after the current has reached a predetermined value during each voltage pulse.

7. The balloon catheter of claim 6, wherein the predetermined value is 50 amps.

8. The balloon catheter of claim 6, wherein the carrier has a guidewire lumen.

9. The balloon catheter of claim 6, wherein the predetermined delay time is 100 nanoseconds or more.

10. A method for delivering shockwaves to a calcified lesion comprising:

advancing a balloon catheter to a calcified lesion, wherein the balloon catheter includes an elongated carrier, a flexible balloon, and a pair of electrodes on the elongated carrier within the balloon, wherein the electrodes are connected to a power source;

activating the power source to supply one or more voltage pulses to the electrodes such that during each pulse, an arc is generated in the balloon and a current flows between the electrodes producing a shockwave;

detecting when the current reaches a predetermined value during each pulse; and

terminating the voltage supplied to the electrodes after the current reaches the predetermined value for that pulse.

11. The method of claim 10, wherein the predetermined value is 50 amps.

12. The method of claim 10, wherein after the detecting step and before the terminating step waiting a predetermined delay time before terminating the voltage supplied to the electrodes.

13. The method of claim 12, wherein the predetermined delay time is 100 nanoseconds or more.

14. A balloon catheter for delivering shockwaves to a calcified lesion comprising:

an elongated carrier;

a flexible balloon mounted on the elongate carrier, said balloon being fillable with a conductive fluid;

a pair of electrodes on the elongated carrier within the balloon; and

a power source coupled to the electrodes for supplying a voltage to the electrodes to generate an arc in the fluid within the balloon and causing current to flow between the electrodes and producing a shockwave;

wherein the power source includes a current sensor for detecting the current flow between the electrodes, and wherein when the current reaches a predetermined value, the sensor generates a signal that causes the power source to terminate the voltage supply to the electrodes and wherein the power source further includes a delay timer with a predetermined delay time, the delay timer being triggered in response to the sensor signal and wherein the voltage supply to the electrodes is terminated after the predetermined delay time has expired.