Cross stream thrombectomy catheter with flexible and expandable cage

• US 20060229645A1
• Filed: 04/07/2005
• Published: 10/12/2006
• Est. Priority Date: 04/07/2005
• Status: Active Grant

• Current Assignee: Boston Scientific Limited (Boston Scientific Corporation)
• Original Assignee: Possis Medical, Inc. (Bayer AG)
• Inventors: Bonnette, Michael J., Thor, Eric J., Janse, Daniel T.
• Granted Patent: US 8,475,487 B2
• Time in Patent Office: Days
• US Class Current: 606/159
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61B 17/320758 with a rotating cutting instrument, e.g. motor driven A61B17/320725, A61B17/32075 and A61B17/320783 take precedence; for removing intra-ocular material A61F9/00763; endoscopic rotatable cutting instruments A61B17/32002
• CPC Class Codes: A61B 2017/22079 with suction of debris
• CPC Class Codes: A61B 2017/22082 after introduction of a substance
• CPC Class Codes: A61B 2017/320004 abrasive
• CPC Class Codes: A61B 2217/005 with suction drainage system
• CPC Class Codes: A61B 2217/007 with irrigation system

Abstract

A cross stream thrombectomy catheter with a flexible and expandable cage preferably formed of nitinol for removal of hardened and aged thrombotic material stubbornly attached to the interior of a blood vessel. The cage, which can be mesh or of straight or spiral filament design, is located close to inflow and outflow orifices at the distal portion of a catheter tube and is deployed and extended at a thrombus site for intimate contact therewith and for action of a positionable assembly and subsequent rotation and lineal actuation to abrade, grate, scrape, or otherwise loosen and dislodge difficult to remove thrombus which can interact with cross stream flows to exhaust free and loosened thrombotic particulate through the catheter tube. An alternative embodiment discloses a mechanism involving a threaded tube in rotatable engagement with an internally threaded sleeve to incrementally control the deployment and expansion of the flexible and expandable cages.

Claims

1. (canceled)

2. A thrombectomy catheter comprising:

a. a catheter tube having a distal end and a proximal end;

b. a porous cage distally located on the catheter tube, the porous cage characterized as capable of radial expansion and radial contraction;

c. a proximally located control means regulating radial expansion and radial contraction of the porous cage;

d. at least one outflow orifice and at least one inflow orifice situated on the catheter tube adjacent the distal end of the catheter; and

,

e. a manifold connected to the proximal end of the catheter tube, the manifold providing for connection to pressurizing and/or evacuation equipment and providing fluid communication with the at least one outflow orifice and the at least one inflow orifice, such that a cross stream jet may be established between the at least one outflow orifice and the at least one inflow orifice.

3. The thrombectomy catheter of claim 2, wherein the at least one outflow orifice and the at least one inflow orifice are located within the porous cage.

4. The thrombectomy catheter of claim 2, wherein the at least one outflow orifice and the at least one inflow orifice are located proximal to the porous cage.

5. The thrombectomy catheter of claim 2, wherein the at least one outflow orifice and the at least one inflow orifice are located distal to the porous cage.

6. The thrombectomy catheter of claim 2, wherein the porous cage is characterized, when radially expanded, by having an external surface suitable for loosening thrombus by converting thrombus to particulate form.

7. The thrombectomy catheter of claim 2, wherein the porous cage includes nitinol.

8. The thrombectomy catheter of claim 7, wherein the nitinol of the porous cage has a preset memory shape, which preset memory shape predisposes the porous cage to radially expand.

9. The thrombectomy catheter of claim 7, wherein the preset memory shape is a heat set memory shape.

10. The thrombectomy catheter of claim 2, wherein the porous cage is a mesh cage.

11. The thrombectomy catheter of claim 10, wherein the porous mesh cage is a porous woven mesh cage.

12. The thrombectomy catheter of claim 2, wherein the porous cage includes a plurality of flexible filaments.

13. The thrombectomy catheter of claim 2, wherein the porous cage, when contracted, includes a plurality of straight filaments, the plurality of straight filaments arranged in a longitudinally oriented parallel manner such that the plurality of straight filaments together define a generally tubular configuration.

14. The thrombectomy catheter of claim 13, wherein the straight filaments of the porous cage are formed of nitinol.

15. The thrombectomy catheter of claim 14, wherein the straight nitinol filaments have a preset memory shape, which preset memory shape predisposes the straight nitinol filaments to assume an arcuate shape and the predisposed arcuate shape of each of the straight nitinol filaments of the plurality being directed such that the porous cage is predisposed to radially expand.

16. The thrombectomy catheter of claim 15, wherein the preset memory shape is a heat set memory shape.

17. The thrombectomy catheter of claim 2, wherein the porous cage, when contracted, includes a plurality of spiral filaments, the plurality of spiral filaments arranged in a helically oriented parallel manner such that the plurality of spiral filaments together define a generally tubular configuration.

18. The thrombectomy catheter of claim 17, wherein the spiral filaments of the porous cage are formed of nitinol.

19. The thrombectomy catheter of claim 18, wherein the spiral nitinol filaments have a preset memory shape, which preset memory shape predisposes the spiral nitinol filaments to a bowed twisted shape and the bowed twisted shape of each of the spiral nitinol filaments of the plurality being directed such that the porous cage is predisposed to radially expand.

20. The thrombectomy catheter of claim 19, wherein the preset memory shape is a heat set memory shape.

21. The thrombectomy catheter of claim 2, wherein the porous cage has a distal end and a proximal end.

22. The thrombectomy catheter of claim 21, wherein expansion of the porous cage includes compression between the distal end and the proximal end of the porous cage.

23. The thrombectomy catheter of claim 21, wherein the distal end of the porous cage is fixed to the catheter tube and the proximal end of the porous cage is free floating and movable along and over the catheter tube.

24. The thrombectomy catheter of claim 2, wherein the proximally located control means includes a manual actuator longitudinally slidable over a proximally located segment of the catheter tube, the manual actuator operating a sheath extending distally over the catheter tube.

25. The thrombectomy catheter of claim 23, wherein the proximally located control means includes a manual actuator longitudinally slidable over a proximally located segment of the catheter tube, the manual actuator operating a sheath extending distally over the catheter tube and connecting to the free floating and movable proximal end of the porous cage.

26. The thrombectomy catheter of claim 2, wherein the proximally located control means includes a mechanism in which a threaded tube rotatingly engages an internally threaded sleeve to rotatably and incrementally operate a sheath, the sheath extending distally over the catheter tube.

27. The thrombectomy catheter of claim 2, wherein the proximally located control means includes a mechanism in which a threaded tube rotatingly engages an internally threaded sleeve to rotatably and incrementally operate a sheath, the sheath extending distally over the catheter tube to the porous cage and wherein the sheath moves incrementally between covering and thereby constraining the porous cage and revealing and thereby deploying the porous cage by allowing the porous cage radially expand.

28. The thrombectomy catheter of claim 27, wherein either the distal end or the proximal end of the porous cage is fixed to the catheter tube and the opposite end of the porous cage is free floating about the catheter tube.

29. The thrombectomy catheter of claim 2, further comprising indicia associated with the proximally located control means, said indicia arranged to coordinate a desired setting of the proximally located control means with a known and indicated specific size parameter of radial expansion of the porous cage.

30. The thrombectomy catheter of claim 2, wherein the proximally located control is mechanically linked to the porous cage by a sheath encasing and movable relative to the catheter tube.

31. The thrombectomy catheter of claim 30, wherein actuation of the manual actuator of the proximally located control moves the sheath such that the proximal and distal ends of porous cage are moved closer together and the porous cage thereby radially expands.

32. The thrombectomy catheter of claim 2, wherein the proximally located control means further includes indicia for aid in selecting a desired degree of expansion of the porous cage.

33. A thrombectomy method for removing resistant thrombus from a resistant thrombus site in vasculature comprising the steps of:

a. providing a catheter having a distally located positionable and radially expandable and contractable porous cage with at least one outflow orifice and at least one inflow orifice associated with the porous cage and a manifold connected to the proximal end of the catheter tube, the manifold providing for connection to pressurizing and/or evacuation equipment and providing fluid communication with the at least one outflow orifice and the at least one inflow orifice;

b. positioning the porous cage, in radially contracted condition, at the thrombus site;

c. radially expanding the porous cage;

d. manipulating the radially expanded porous cage against the resistant thrombus so as to disrupt and loosen portions of the thrombus as thrombus particulates;

e. establishing a cross stream flow between the at least one outflow orifice and the at least one inflow orifice;

f. entraining the disrupted and loosened portions of the thrombus as thrombus particles in the cross stream flow; and

,

g. evacuating at least a portion of the cross stream flow with entrained thrombus particles through the manifold.

34. The thrombectomy method of claim 33, wherein the radial expansion and contraction of the porous cage is controlled by a proximal control on the catheter tube.

35. The thrombectomy method of claim 34, wherein the radial expansion and contraction is conveyed from the proximal control to the porous cage by a movable sheath located about the catheter tube.

36. The thrombectomy method of claim 35, wherein the porous cage is bias and predisposed to radial expansion and the sheath encases and constrains the porous cage.

37. The thrombectomy method of claim 35, wherein the porous cage has a distal end and a proximal end and the sheath regulates the spacing being the proximal end and the distal end of the porous cage.

38. The thrombectomy method of claim 34, wherein the proximal control includes indicia for aid in selecting a desired degree of expansion of the porous cage.

39. A method of making a porous cage for a thrombectomy catheter comprising the steps of:

a. providing a tube having a proximal end and a distal end; and

,

b. cutting the tube to form a plurality of filaments extending between the proximal end and the distal end.

40. The method of claim 39, wherein the filaments are straight.

41. The method of claim 39, wherein the filaments are spiral.

42. The method of claim 39, wherein the tube is formed of nitinol.

43. The method of claim 42, further comprising the step of presetting an expanded memory shape in the filaments.