Methods and apparatus for treating embolism

• US 9,717,519 B2
• Filed: 05/20/2016
• Issued: 08/01/2017
• Est. Priority Date: 11/20/2012
• Status: Active Grant

• Current Assignee: Inari Medical, Inc.
• Original Assignee: Inceptus Medical, Llc
• Inventors: Cox, Brian J., Lubock, Paul, Rosenbluth, Robert F.
• Primary Examiner(s): MILES, JONATHAN WADE
• Application Number:
  US15/159,989
• Publication Number:
  US 20160262790A1
• Time in Patent Office: 438 Days
• CPC Class Codes: A61B 17/22032 having inflatable gripping elements balloon catheters A61M25/10
• 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 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61B 17/32075 Pullback cutting; combined forward and pullback cutting, e.g. with cutters at both sides of the plaque
• CPC Class Codes: A61B 2017/00809 Lung operations
• CPC Class Codes: A61B 2017/00862 elastic or resilient for sutures A61B2017/0618
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2017/22034 for gripping the obstruction or the tissue part from inside
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22081 Treatment of vulnerable plaque
• CPC Class Codes: A61B 2017/22094 for crossing total occlusions, i.e. piercing
• CPC Class Codes: A61B 2017/320716 comprising means for preventing embolism by dislodged material
• CPC Class Codes: A61B 2217/005 with suction drainage system
• CPC Class Codes: A61M 39/04 having pierceable self-sealing members

Abstract

A method and apparatus for treating a clot in the blood vessel of a patient, and particularly the treatment of a pulmonary embolism is disclosed. The treatment includes restoring flow through the clot followed by clot removal, either partially or substantially completely. The clot treatment device is expandable into the blood vessel and may contain radial extensions that assist in restoring flow as well as in removing clot material.

Claims

1. A method of treating an embolism comprising:

delivering an embolectomy device through the vasculature to an embolism that at least partially restricts blood flow through a vessel, wherein the embolectomy device comprises an expandable cylindrical section and at least first and second radial expansion members configured to expand outwardly from the cylindrical section, wherein the cylindrical section is between the first and second radial expansion members;

deploying the embolectomy device within the embolism so as to restore blood flow through the embolism,

wherein deploying the embolectomy device comprises expanding the cylindrical section within the embolism such that the cylindrical section forms an expanded flow channel through the embolism and expanding the radial expansion member to a greater extent than the cylindrical section, and wherein at full expansion of the cylindrical member the radial expansion member projects outward from the cylindrical member, and wherein the cylindrical section has a first length in a longitudinal direction and each of the first and second radial expansion members have a length in the longitudinal direction that is less than the first length of the cylindrical section at full expansion;

moving the embolectomy device and at least a portion of the embolism along the vessel; and

withdrawing the embolectomy device and at least a portion of the embolism from the vessel.

2. A method according to claim 1 wherein deploying the embolectomy device comprises expanding a plurality of radial extensions of the embolectomy device.

3. A method according to claim 2 wherein at least one of the plurality of radial extensions is expanded distal to the embolism.

4. A method according to claim 1 wherein deploying the embolectomy device comprises expanding a plurality of cylindrical portions and a plurality of radial expansion members of the device, and wherein the cylindrical portions are between the radial expansion members causing filaments of the clot treatment device to change angle with respect to an axis of the device and thereby increase adherence of material of the embolism to the clot treatment device.

5. A method according to claim 4 wherein the embolectomy device comprises a continuous mesh and the cylindrical portions and the radial expansion members are integrally formed of the mesh, and expanding the plurality of radial expansion members and the cylindrical portions comprises expanding the mesh to a greater extent at the radial expansion members than at the cylindrical portions.

6. A method according to claim 4 wherein deploying the embolectomy device comprises expanding the device such that a surface area of the embolectomy device expands within a range of at least two times to four times the surface area of a uniformly cylindrical device.

7. A method according to claim 1, wherein deploying the embolectomy device comprises causing filaments of the embolectomy device to change angle with respect to an axis of the device and thereby increase adherence of material of the embolism to the embolectomy device.

8. A method according to claim 1, further comprising applying vacuum during retracting of the embolectomy device.

9. A method according to claim 1 wherein the cylindrical section and the radial expansion member are self-expanding.

10. A method of treating an embolism comprising:

accessing a blood vessel of a patient;

inserting a catheter into the blood vessel and urging the catheter through the blood vessel and into an artery until a distal end of the catheter is located at a distal end region of an embolism of the patient;

delivering a clot treatment device having a flow portion and at least first and second radial expansion members through the catheter and into the embolism, wherein the flow portion is between the first and second radial expansion members;

expanding the flow portion from a compressed state to an expanded state such that a diameter of the flow portion increases by a ratio of at least 4;

1 to 8;

1 and

thereby forms a flow channel that restores blood flow through the embolism;

expanding the radial expansion member to a greater extent than the diameter of the flow portion in the expanded state, and wherein at full expansion of the flow portion the radial expansion member projects outward from the flow portion, and wherein the flow portion has a first length in a longitudinal direction and each of the first and second radial expansion members have a length in the longitudinal direction that is less than the first length of the flow portion at full expansion;

retracting the clot treatment device and at least a portion of the clot material along the vessel.

11. A method according to claim 10 wherein the device includes a plurality of radial expansion members and the method comprises expanding the plurality of radial expansion members to a greater extent than the flow portion.

12. A method according to claim 11 wherein at least one of the plurality of radial extensions is expanded distal to the embolism.

13. A method according to claim 11 wherein expanding the flow portion and the radial expansion member comprises causing filaments of the clot treatment device to change angle with respect to an axis of the device and thereby increase adherence of material of the embolism to the clot treatment device.

14. A method according to claim 11, further comprising applying vacuum during retracting of the expanded clot treatment device.

15. A method according to claim 11 wherein the flow portion and the radial expansion member are self-expanding.

16. A method according to claim 11 wherein expanding of the embolectomy device comprises expanding the device such that a surface area of the clot treatment device expands within a range of at least two times to four times the surface area of a uniformly cylindrical device.

17. A method according to claim 11 wherein expanding includes expanding a portion of the clot treatment device distal to the embolism.

18. A method according to claim 17, wherein expanding includes expanding the clot treatment device so that it exceeds the length of the embolism.

19. A method according to claim 11 wherein restoring of the blood flow reduces a mean resting arterial pressure within a range of about 20-50 mmHg.

20. A method of treating an embolism comprising:

accessing a blood vessel of a patient;

inserting a delivery catheter containing a clot treatment device into the blood vessel, through the circulatory system of the patient, and to a clot of an embolism;

urging the delivery catheter through the clot;

deploying the clot treatment device from the delivery catheter and causing an outwardly expanding radial force along a cylinder to be urged against an inner surface of the clot to form a channel entirely through the clot and causing at least first and second radial expansion members to expand to a greater extent than the channel, wherein the cylinder is between the first and second radial expansion members, and wherein at full expansion the cylinder has a first length in a longitudinal direction, the first and second radial expansion members project outward from the cylinder, and each the first and second radial expansion members have a length in the longitudinal direction that is less than the first length of the cylinder; and

withdrawing the clot treatment device through the clot and thereby removing clot material from the clot.

21. A method according to claim 20 wherein the outwardly expanding radial force comprises generating a force that varies in magnitude along a length of the clot treatment device.

22. A method according to claim 21 wherein the variation in magnitude is a result of a plurality of radial expansion members expanding along an axis of the clot retrieval device.

23. A method according to claim 21 wherein generating of a force that varies in magnitude comprises expanding radial expansion members thereon in the clot.

24. A method according to claim 20 wherein causing the outwardly expanding radial force is comprised of expanding the cylinder of the clot treatment device in the clot.

25. A method according to claim 20 wherein withdrawing the clot treatment device includes elongating the clot treatment device as the clot treatment device contacts material of the clot.

26. A method according to claim 20 wherein deploying of the clot treatment device includes cutting into material of the clot.

27. A method according to claim 20 wherein deploying of the clot treatment device includes causing filaments of the clot treatment device to change angle with respect to an axis of the device and thereby increase adherence of material of the clot to the clot treatment device.

28. A method according to claim 20, wherein the cylinder and the radial expansion member are self-expanding.

29. A method according to claim 20, further comprising applying vacuum during the withdrawing of the clot treatment device.

30. A method according to claim 20 wherein deploying of the clot treatment device includes increasing blood flow rate through the clot by at least about 50 ml/min.

31. A device for treating an embolism that at least partially restricts blood flow through a vessel, the device comprising:

an elongated shaft having a proximal region and a distal region;

an expandable braid attached to the distal region of the elongated shaft, the braid having a plurality of radially extending portions and at least one cylindrical portion, and the radially extending portions and the cylindrical portion being configured to move from a compressed state sized to fit in a delivery catheter to an expanded state;

wherein the cylindrical portion is between a pair of the radially extending portions, and in the expanded state the cylindrical portion is configured to press radially outward against the embolism;

wherein the radially extending portions extend radially outward from the cylindrical portion in the expanded state such that portions of the embolism are retained between the radially extending portions; and

wherein the cylindrical portion has a first length along a longitudinal direction of the braid in the expanded state and the radially extending portions have a second length along the longitudinal direction of the braid in the expanded state that is less that the first length.

32. The device of claim 31 wherein at least a portion of the individual radially extending portions is disk-shaped.

33. The device of claim 31 wherein the individual radially extending portions include a curved portion and a linear portion.

34. The device of claim 31 wherein, in the expanded state, an exterior surface area of the device is at least two times to four times greater than the surface area of a uniformly cylindrical device.

35. The device of claim 31 wherein the braid includes a plurality of filaments, and wherein:

in the delivery state, the filaments form a first angle with respect to an axis of the device; and

in the expanded state, the filaments form a second angle with respect to an axis of the device that is different than the first angle.

36. The device of claim 31 wherein at least one of the radially extending portions is tapered.

37. The device of claim 31 wherein at least one of the radially extending portions is generally cylindrical.

38. The device of claim 31 wherein the individual radially expanding portions have a first diameter and a second diameter different than the first diameter.

39. The device of claim 31 wherein the expandable braid comprises metallic filaments of Nitinol.

40. The device of claim 31 wherein at least one generally cylindrical portion forms a conical lumen.

41. The device of claim 31 wherein individual radially extending portions have a flare-shaped cross-section with a concave proximal surface.

42. The device of claim 31 wherein at least one of the radially extending portions has a generally triangular cross-section.