Method and apparatus for treating valvular disease

• US 10,736,603 B2
• Filed: 04/01/2016
• Issued: 08/11/2020
• Est. Priority Date: 04/02/2015
• Status: Active Grant

• Current Assignee: Cardiawave SA
• Original Assignee: Cardiawave SA
• Inventors: Messas, Emmanuel, Pernot, Mathieu, Tanter, Mickael, Villemain, Olivier
• Primary Examiner(s): Jacob, Oommen
• Application Number:
  US15/557,455
• Publication Number:
  US 20180064412A1
• Time in Patent Office: 1,593 Days
• Field of Search: 600439, 600437, 600407
• CPC Class Codes: A61B 17/22004 using mechanical vibrations, e.g. ultrasonic shock waves A61B17/225 takes precedence
• CPC Class Codes: A61B 17/225 for extracorporeal shock wave lithotripsy [ESWL], e.g. by using ultrasonic waves
• CPC Class Codes: A61B 2017/00398 using powered actuators, e.g. stepper motors, solenoids
• CPC Class Codes: A61B 2017/22098 Decalcification of valves
• CPC Class Codes: A61B 2034/2063 Acoustic tracking systems, e.g. using ultrasound
• CPC Class Codes: A61B 2034/2065 Tracking using image or pattern recognition
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 2090/378 using ultrasound
• CPC Class Codes: A61B 2090/3782 transmitter or receiver in catheter or minimal invasive instrument
• CPC Class Codes: A61B 2090/3784 both receiver and transmitter being in the instrument or receiver being also transmitter
• CPC Class Codes: A61B 2576/023 for the heart
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 5/0053 by applying pressure, e.g. compression, indentation, palpation, grasping, gauging
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 8/04 Measuring blood pressure
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/4483 : characterised by features of the ultrasound transducer
• CPC Class Codes: A61B 8/485 : involving measuring strain or elastic properties
• CPC Class Codes: A61B 8/488 : involving Doppler signals
• CPC Class Codes: A61N 2007/0004 : Applications of ultrasound therapy
• CPC Class Codes: A61N 2007/0039 : using microbubbles
• CPC Class Codes: A61N 2007/0052 : using the same transducer for therapy and imaging
• CPC Class Codes: A61N 2007/0086 : Beam steering
• CPC Class Codes: A61N 2007/0095 : by modifying an excitation signal
• CPC Class Codes: A61N 7/00 : Ultrasound therapy lithotripsy A61B17/22, A61B17/225; massage using supersonic vibration A61H23/00 ; using ultrasound for introducing media into the body A61M37/0092
• CPC Class Codes: A61N 7/02 : Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: G16H 30/40 : for processing medical images, e.g. editing

Abstract

An apparatus for treating or preventing a valvular disease comprises: a ultrasound probe located externally to a heart of patient, able to produce ultrasound waves focused inside the heart and suitable to generate, at a focal spot, a pressure sufficient to result in cavitation, an imaging device for mapping in real time a treatment region of a cardiac valve of the patient, the treatment region comprising at least one leaflet of the cardiac valve, a controller configured for driving the ultrasound probe to emit a sequence of focused ultrasound waves, the controller being further configured for steering the focused ultrasound waves so as to scan the entire treatment region to soften the tissues of the treatment region. A method for treating or preventing valvular disease, carried out using the apparatus is also provided.

Claims

1. An apparatus for treating or preventing valvular stenosis, said apparatus comprising:

an ultrasound probe located externally to a heart of patient, able to produce ultrasound waves focused inside said heart and suitable to generate, at a focal spot, a pressure sufficient to result in cavitation,

an imaging device for mapping in real time a treatment region of a cardiac valve of the patient, said treatment region comprising at least one leaflet of the cardiac valve,

a controller configured for driving the ultrasound probe to emit a sequence of focused ultrasound waves in such a way that a duration of a pressure pulse generated by each focused ultrasound wave of the sequence of focused ultrasound waves is less than 80 microseconds, and in such a way that each of them generates at a focal spot a peak negative pressure half-cycle that exceeds a peak negative pressure of 5 MPa and/or a peak positive pressure half-cycle that exceeds a peak positive pressure of 10 MPa,

the controller being further configured for estimating in real-time a motion of the treatment region from images acquired by said imaging device, and for steering the focused ultrasound waves emitted by the ultrasound probe in function of said motion of the treatment region to scan the entire treatment region;

the apparatus further comprising a measuring device suitable for measuring an index of valvular stenosis after having controlled the ultrasound probe to emit the sequence of N focused ultrasound waves, the controller being further configured for reiterating the steps of controlling the ultrasound probe to emit a sequence of focused ultrasound waves and measuring said index of valvular stenosis until said index crosses a predefined threshold.

2. The apparatus according to claim 1, further comprising a robotic arm carrying said ultrasound probe, the controller being configured for driving the robotic harm to control the location of the ultrasound probe externally to the heart of the patient so as to keep the treatment region inside a scannable region of the ultrasound probe.

3. The apparatus according to claim 1, wherein said measuring device is a Doppler imager configured for measuring a hemodynamic parameter, said index of valvular stenosis being a function of said hemodynamic parameter.

4. The apparatus according to claim 1, wherein said measuring device is an imaging device configured for detecting and estimating a valve motion parameter, said index of valvular stenosis being a function of said valve motion parameter.

5. The apparatus according to claim 1, wherein said measuring device is a shear wave imager configured for measuring a shear wave propagation parameter, said index of valvular stenosis being a function of said shear wave propagation parameter.

6. The apparatus according to claim 1, wherein the controller is configured for driving the ultrasound probe to emit said sequence of focused ultrasound waves at a rate between 20 and 5000 shots per seconds.

7. The apparatus according to claim 1, wherein the controller is configured for steering the focused ultrasound waves so as to move their focal spot at a travelling speed comprised between 0.1 mm/s and 10 mm/s.

8. The apparatus according to claim 1, wherein the controller is configured for steering the focused ultrasound waves in such a way that a point of the treatment region is included in the focal spots of a number M of focused ultrasound waves of the sequence of focused ultrasound waves, said number M being comprised between 1 and 1000, preferably between 2 and 1000, even more preferably between 15 and 150.

9. The apparatus according to claim 1, wherein the controller is configured for steering the focused ultrasound waves in such a way that the focal spots of the sequence of focused ultrasound waves are separated from one another by a minimal distance larger than 0.1 millimetres.

10. The apparatus according to claim 1, wherein the controller is configured for driving the ultrasound probe in such a way that a duration of a pressure pulse generated by each focused ultrasound wave of the sequence of focused ultrasound waves is less than 20 microseconds.

11. The apparatus according to claim 1, wherein the ultrasound probe comprises a plurality of transducers within a reflective cavity, and wherein the controller is configured for driving at least one said transducer to emit an emission signal in the reflective cavity, the duration of said emission signal being less than 10 milliseconds, preferably less than 1 millisecond.

12. The apparatus according to claim 1, wherein the controller is further configured for receiving an electrocadiography signal and for driving the ultrasound probe to emit the sequence of focused ultrasound waves during specific moments in a cardiac cycle, determined from said electrocardiography signal.

13. A method for treating or preventing valvular stenosis comprising:

providing an ultrasound probe located externally to a heart of a patient and able to produce ultrasound waves focused inside said heart, mapping a treatment region of a cardiac valve of the patient, said treatment region comprising at least one leaflet of the cardiac valve, controlling the ultrasound probe to emit a sequence of N focused ultrasound waves, wherein each focused ultrasound wave of the sequence of N focused ultrasound waves generates a pressure sufficient to result in cavitation at a focal spot of said focused ultrasound wave, wherein the focal spots of the sequence of N focused ultrasound waves scan the entire treatment region to soften the tissues of the treatment region;

wherein the duration of a pressure pulse generated by each focused ultrasound wave of the sequence of focused ultrasound waves is less than 80 microseconds, and wherein each focused ultrasound wave of the sequence of focused ultrasound waves generates at a focal spot a peak negative pressure half-cycle that exceeds a peak negative pressure of 5 MPa and/or a peak positive pressure half-cycle that exceeds a peak positive pressure of 10 MPa.

14. The method according to claim 13, wherein said step of controlling the ultrasound probe to emit a sequence of N focused ultrasound waves comprises:

emitting the sequence of focused ultrasound waves at a predefined rate of emission, and moving the focal spot of the focused ultrasound waves to scan the entire treatment region.

15. The method according to claim 13, wherein said predefined rate of emission is comprised between 20 and 5000 shots per seconds.

16. The method according to claim 14, wherein the focal spot of the focused ultrasound waves is moved with a predefined travelling speed, said predefined travelling speed being comprised between 0.1 mm/s and 10 mm/s.

17. The method according to claim 13, wherein the focused ultrasound waves emitted by the ultrasound probe are steered to scan the entire treatment region.

18. The method according to claim 17, wherein the sequence of N focused ultrasound waves is such that a point of the treatment region is included in the focal spots of a number M of focused ultrasound waves of the sequence of focused ultrasound waves, said number M being comprised between 1 and 1000.

19. The method according to claim 18, wherein the sequence of N focused ultrasound waves is such that a point of the treatment region is included in the focal spots of a number M of focused ultrasound waves of the sequence of focused ultrasound waves, said number M being comprised between 15 and 150.

20. The method according to claim 13, wherein the focal spots of the sequence of focused ultrasound waves are separated from one another by a minimal distance larger than 0.1 millimetres.

21. The method according to claim 13, wherein the treatment region covers a surface of at least 9 square millimetres, measured in a plane perpendicular to an opening direction of the cardiac valve.

22. The method according to claim 13, further comprising:

measuring an index of valvular stenosis after having controlled the ultrasound probe to emit the sequence of N focused ultrasound waves, and, until said index crosses a predefined threshold, reiterating the steps of controlling the ultrasound probe to emit a sequence of N focused ultrasound waves and measuring said index of valvular stenosis.

23. The method according to claim 22, wherein said index of valvular stenosis is function of a hemodynamic parameter and the step of measuring said index of valvular stenosis comprises Doppler imaging.

24. The method according to claim 22, wherein said index of valvular stenosis is function of a valve motion parameter and the step of measuring said index of valvular stenosis comprises estimation of valve motion.

25. The method according to claim 22, wherein said index of valvular stenosis is function of a shear wave propagation parameter and the step of measuring said index of valvular stenosis comprises shear wave imaging.

26. The method according to claim 13, further comprising imaging the treatment region of the cardiac valve in real-time by ultrasound imaging.

27. The method according to claim 13, further comprising mechanically controlling a location of the ultrasound probe externally to the heart of the patient to keep the treatment region inside a scannable region of the ultrasound probe.

28. The method according to claim 13, wherein a motion of the treatment region comprising at least one leaflet of the cardiac valve is estimated in real-time by ultrasound imaging and the focused ultrasound waves emitted by the ultrasound probe are steered in function of said motion of the treatment region to scan the entire treatment region.

29. The method according to claim 13, wherein the duration of a pressure pulse generated by each focused ultrasound wave of the sequence of focused ultrasound waves is less than 20 microseconds.

30. The method according to claim 13, wherein each focused ultrasound wave of the sequence of focused ultrasound waves is generated by controlling at least one transducer of the ultrasound probe to emit an emission signal in a reflective cavity of the ultrasound probe, the duration of said emission signal being less than 10 milliseconds, preferably less than 1 millisecond.

31. The method according to claim 13, wherein the treatment region further comprises at least one portion of an annulus of the cardiac valve.

32. The method according to claim 13, wherein said valvular disease is valvular stenosis.