Electrically enhanced retrieval of material from vessel lumens

• US 10,709,463 B2
• Filed: 12/11/2017
• Issued: 07/14/2020
• Est. Priority Date: 12/11/2017
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Girdhar, Gaurav, Nguyen, Dinh, Nguyen, Hoai
• Primary Examiner(s): Templeton, Christopher L
• Assistant Examiner(s): Restaino, Andrew P.
• Application Number:
  US15/838,230
• Publication Number:
  US 20190175200A1
• Time in Patent Office: 946 Days
• Field of Search: 606127
• CPC Class Codes: A61B 17/22031 Gripping instruments, e.g. forceps, for removing or smashing calculi A61B17/221 takes precedence
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 18/08 by means of electrically-heated probes
• CPC Class Codes: A61B 18/10 Power sources therefor
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments
• CPC Class Codes: A61B 2017/00929 isolating electrical current
• CPC Class Codes: A61B 2017/22034 for gripping the obstruction or the tissue part from inside
• CPC Class Codes: A61B 2017/22042 Details of the tip of the guide wire
• CPC Class Codes: A61B 2017/2215 having an open distal end
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/00345 Vascular system
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/9511 the retaining means being filaments or wires
• CPC Class Codes: A61F 2002/9528 for retrieval of stents

Abstract

Retrieval of material from vessel lumens can be improved by electrically enhancing attachment of the material to the removal device. The removal device can have a core assembly that includes a hypotube coupled to a first electrical terminal and a pushwire coupled to a second electrical terminal, the pushwire extending through the hypotube lumen. An insulating layer separates the hypotube and the pushwire, and an interventional element is coupled to a distal end of the pushwire. The interventional element can be disposed adjacent to a thrombus. An electrical signal is delivered to the interventional element to promote adhesion of the thrombus to the interventional element. The electrical signal can optionally be a periodic waveform, and the total energy delivered can be between 0.75-24,000 mJ and the peak current delivered via the electrical signal can be between 0.5-5 mA.

Claims

1. A method for thrombectomy, comprising:

disposing an interventional element adjacent to a thrombus within a blood vessel;

promoting adhesion of the thrombus to the interventional element by delivering an electrical signal to the interventional element, the electrical signal comprising a periodic waveform,

wherein the waveform comprises a composite waveform including a superposition of a non-square waveform having a first peak current and a square waveform having a second peak current that is less than the first peak current,

wherein a total energy delivered via the electrical signal is between 0.75-24,000 mJ, and

wherein the first peak current is between 0.5-5 mA.

2. The method of claim 1, wherein the electrical signal is delivered for no more than 2 minutes.

3. The method of claim 1, wherein the total energy delivered via the electrical signal is between 120-5000 mJ.

4. The method of claim 1, wherein a total charge delivered via the electrical signal is between 30-1200 mC.

5. The method of claim 4, wherein the total charge delivered via the electrical signal is between 120-160 mC.

6. The method of claim 1, wherein a frequency of the electrical signal is between 1 Hz to 1 MHz.

7. The method of claim 6, wherein the frequency of the electrical signal is between 1 Hz to 1 kHz.

8. The method of claim 1, wherein a duty cycle of the electrical signal is between 5-99%.

9. The method of claim 8, wherein the duty cycle of the electrical signal is between 5-20%.

10. The method of claim 1, wherein the first peak current is at least 5 times greater than the second peak current.

11. The method of claim 1, wherein the first peak current is applied for a shorter duration of time than the second peak current.

12. The method of claim 1, wherein the non-square waveform comprises a triangular waveform.

13. The method of claim 1, wherein the interventional element comprises an electrically conductive self-expandable device.

14. The method of claim 1, further comprising removing the thrombus from the blood vessel.

15. The method of claim 1, further comprising retracting the interventional element, thereby displacing the thrombus.

16. The method of claim 1, wherein delivering the composite waveform to the interventional element is not significantly thrombogenic.

17. The method of claim 1, wherein the interventional element comprises a stent retriever.

18. The method of claim 1, wherein the interventional element comprises a thrombectomy device.

19. The method of claim 1, wherein the interventional element comprises a removal device.

20. The method of claim 1, wherein the interventional element comprises a catheter.

21. The method of claim 1, wherein the first peak current precedes the second peak current.

22. A method for thrombectomy, comprising:

positioning an interventional element proximate to a thrombus, the interventional element in electrical communication with a power source;

supplying an electrical composite waveform from the power source to the interventional element, the composite waveform comprising a combination of a first waveform having a first peak current and a second waveform having a second peak current that is less than the first peak current, wherein the second peak current is applied for a shorter duration of time than the first peak current,

wherein a total charge supplied via the composite waveform is between 30-240 mC, and

wherein the composite waveform is supplied for no more than 2 minutes.

23. The method of claim 22, wherein a total energy delivered via the composite waveform is between 120-24,000 mJ.

24. The method of claim 23, wherein the total energy supplied via the composite waveform is between 120-5000 mJ.

25. The method of claim 22, wherein the total charge delivered via the composite waveform is between 30-1200 mC.

26. The method of claim 25, wherein the total charge delivered via the composite waveform is between 120-160 mC.

27. The method of claim 22, wherein the first waveform comprises a non-square waveform.

28. The method of claim 22, wherein the first peak current is at least 5 times greater than the second peak current.

29. The method of claim 22, wherein the first waveform comprises a triangle waveform.

30. The method of claim 22, wherein delivering the composite waveform to the interventional element is not significantly thrombogenic.

31. The method of claim 22, wherein the first peak current precedes the second peak current.