Infusion flow guidewire system

• US 20080312671A1
• Filed: 10/30/2007
• Published: 12/18/2008
• Est. Priority Date: 06/12/2007
• Status: Active Grant

• Current Assignee: Boston Scientific Medical Device Limited (Boston Scientific Corporation)
• Original Assignee: Possis Medical, Inc. (Bayer AG)
• Inventors: Le, Hieu V., Bonnette, Michael J., Ball, Douglas J., Thor, Eric J., Teschendorf, John L., Riles, John C.
• Granted Patent: US 8,608,703 B2
• Time in Patent Office: Days
• US Class Current: 606/159
• CPC Class Codes: A61B 17/32037 for removing obstructions from inner organs or blood vessels, e.g. for atherectomy
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22049 Means for locking the guide wire in the catheter
• CPC Class Codes: A61M 2025/09083 having a coil around a core

Abstract

An infusion flow guidewire system including a delivery sheath and an infusion flow guidewire. The minimal cross section flexible infusion flow guidewire includes a nitinol hypotube, a flexible tip and distally located rearwardly directed orifices for infusion of fibrinolytics and for introduction of high pressure fluids for maceration and rearwardly directed flow of thrombus debris located in tortuous small sized vessels. Apparatus, some of which is removably attachable, is provided for grasping members of the invention for rotational torquing and for longitudinal actuation along and within the vasculature.

Claims

1. An infusion flow guidewire comprising:

a. a flexible hypotube having a lumen, a proximal end, and a distal end, the flexible hypotube further having a drawn hypotube section, the drawn hypotube section characterized by a diameter less than the flexible hypotube, the drawn hypotube section located at the distal end of the flexible hypotube;

b. a reinforcement collar, the reinforcement collar aligned and secured over a region of the drawn hypotube section with the drawn hypotube section of the flexible tube extending through the reinforcement collar;

c. at least one proximally directed jet orifice in the reinforcement collar, the at least one jet orifice comprising a hole in the reinforcement collar and a hole in the wall of the drawn hypotube section, aligned therewith, so as to allow fluid communication from the lumen of the drawn hypotube section of the flexible hypotube;

d. a flexible coil attached to and extending distally from the reinforcement collar, the flexible coil aligned over and about a portion of the hypotube section extending distally from the reinforcement collar;

e. a core wire secured to the drawn hypotube section and extending distally from the drawn hypotube section, the core wire having a proximal end located distally of the reinforcement collar, the core wire coaxially aligned within the flexible coil and having a proximally located round section, a distally located flat section and a tapered transition section therebetween, the distal end of the core wire terminating in a weld to the distal end of the flexible coil; and

,

f. wherein the flexible coil located distal of the drawn hypotube section and the core wire located distal of the drawn hypotube section and the weld therebetween together define a flexible tip.

2. The infusion flow guidewire of claim 1, wherein the flexible hypotube is formed of nitinol.

3. The infusion flow guidewire of claim 1, wherein the reinforcement collar is formed of nitinol.

4. The infusion flow guidewire of claim 1, wherein the reinforcement collar is secured to the drawn hypotube section of the flexible hypotube by at least one laser weld.

5. The infusion flow guidewire of claim 4, wherein the at least one laser weld is one of two laser welds securing the reinforcement collar to the drawn hypotube section and the two laser welds are located near the distal end and near the proximal end of the reinforcement collar.

6. The infusion flow guidewire of claim 1, wherein the hole in reinforcement collar and the hole in the drawn hypotube section are formed by electrical discharge machining.

7. The infusion flow guidewire of claim 1, wherein the flexible coil is formed of platinum.

8. The infusion flow guidewire of claim 1, wherein the core wire is formed of stainless steel.

9. The infusion flow guidewire of claim 1, wherein the core wire is gold plated.

10. The infusion flow guidewire of claim 1, wherein the core wire is secured to the inner wall surface of the drawn hypotube section.

11. The infusion flow guidewire of claim 1, wherein the core wire is secured to the inner wall surface of the drawn hypotube section by at least one laser swage.

12. The infusion flow guidewire of claim 1, wherein the flexible tip is more flexible than the drawn hypotube section.

13. The infusion flow guidewire of claim 1, wherein the flexible hypotube has an outer diameter of about 0.014 inch.

14. The infusion flow guidewire of claim 1, wherein the flexible hypotube has an inner diameter of about 0.010 inch.

15. The infusion flow guidewire of claim 1, wherein the reinforcement collar has an outer diameter of about 0.014 inch.

16. The infusion flow guidewire of claim 1, wherein the reinforcement collar has an inner diameter of about 0.010 inch.

17. The infusion flow guidewire of claim 2, wherein the flexible hypotube has a proximal extension of stainless steel tubing.

18. An infusion flow guidewire system comprising:

a. an infusion flow guidewire, having a proximal end, a distal end, at least one jet orifice, and a flexible tip at the distal end;

b. a delivery sheath having a proximally located torque handle, the infusion flow guidewire capable of passing through the delivery sheath; and

,

c. a coupling assembly removably attachable to the proximal end of the infusion flow guidewire so as to facilitate connection of the proximal end of the infusion flow guidewire to a pressurized fluid supply and to facilitate manipulation of the infusion flow guidewire.

19. The infusion flow guidewire system of claim 18, wherein the delivery sheath has an outer diameter of 0.035 inch.

20. The infusion flow guidewire system of claim 18, wherein the delivery sheath has an inner diameter of 0.017 inch.

21. The infusion flow guidewire system of claim 18, wherein the delivery sheath is formed of polyimide.

22. The infusion flow guidewire system of claim 21, wherein the delivery sheath is formed of braided polyimide.

23. The infusion flow guidewire system of claim 18, wherein the torque handle of the delivery sheath includes:

i. a torque body, having a bore and external threads;

ii. a collet, for insertion into the bore of the torque body;

iii. a collet nut, for compressing the collet when tightened on the external threads; and

,

iv. a strain relief having a passage carrying the proximal end of the delivery sheath;

wherein the assembled torque handle provides coaxial accommodation of the delivery sheath and frictional engagement of the infusion flow guidewire when tightened.

24. The infusion flow guidewire system of claim 18, wherein the coupling assembly includes:

i. a generally stationary proximal knob and a rotatable distal knob, the proximal knob providing removable connection to the distal end of a pressure fluid supply and the proximal knob providing removable attachment to the proximal end of the infusion flow guidewire;

ii. a threaded insert;

iii. a threaded body interacting with the threaded insert;

iv. an O-ring;

v. a compression fixture; and

,

vi. a tube collet;

wherein rotatably tightening the rotatable distal knob relative to the generally stationary proximal knob causes the threaded insert, the threaded body and the compression fixture to interact to compress the o-ring to seal about the proximal end of the infusion flow guidewire.

25. A method of removing thrombus from vasculature, the method comprising the steps of:

a. providing a delivery sheath, the delivery sheath having a proximal end and a distal end, and providing an infusion flow guidewire, the infusion flow guidewire having a proximal end and a distal end, the distal end including a flexible tip and having at least one proximally directed jet orifice adjacent the flexible tip, the infusion flow guidewire capable of passing through the delivery sheath;

b. maneuvering the delivery sheath through the vasculature to position the distal end of the delivery sheath near the thrombus to be removed;

c. inserting the infusion flow guidewire into the delivery sheath; and

,

d. positioning the jet orifice adjacent the flexible tip of the infusion flow guidewire in the thrombus to be removed and expelling fluid from the at least one proximally directed jet orifice to act upon the thrombus so as to remove thrombus by action of fluid expelled from the jet orifice.

26. The method of claim 25, wherein the step of inserting the infusion flow guidewire into the delivery sheath precedes the step of maneuvering the delivery sheath through the vasculature to position the distal end of the delivery sheath near the thrombus to be removed.

27. The method of claim 25, wherein the step of inserting the infusion flow guidewire into the delivery sheath follows the step of maneuvering the delivery sheath through the vasculature to position the distal end of the delivery sheath near the thrombus to be removed.

28. The method of claim 25, further comprising the steps of:

e. removing the delivery sheath while leaving the infusion flow guidewire in the vasculature; and

,

f. installing another device over the infusion flow guidewire.

29. The method of claim 28, wherein the another device is a stent.

30. The method of claim 28, wherein the another device is an aspiration catheter.

31. The method of claim 25, wherein the proximal end of the infusion flow guidewire is connected to a pressure fluid source.

32. The method of claim 31, wherein the pressure fluid source is a high pressure source.

33. The method of claim 32, wherein the high pressure fluid source is capable of a pressure of up to about 20 kpsi.

34. The method of claim 32, wherein the high pressure fluid source is applied in pulses.

35. The method of claim 25, wherein the step of positioning the at least one jet orifice adjacent the flexible tip of the infusion flow guidewire in the thrombus to be removed and expelling fluid from the at least one proximally directed jet orifice to act to remove thrombus by action of fluid expelled from the jet orifice is accompanied by at least one additional actuation motion of the infusion flow guidewire.

36. The method of claim 35, wherein the at least one accompanying additional actuation motion is selected from the group consisting of to and fro motion and rotary motion.

37. The method of claim 25, wherein the expelled fluid includes fibrinolytic agents.

38. An infusion flow guidewire system comprising a flexible infusion flow guidewire, said guidewire including an elongated flexible hypotube for delivering a pressurized liquid to a thrombus in a vessel or artery, said guidewire having a flexible tip section, said elongated flexible hypotube having a proximal end and a distal end, said elongated flexible hypotube having a plurality of jet orifices near said distal end for expelling said pressurized liquid therefrom, a torque handle having a distal end and a proximal end, said torque handle being connected to said elongated flexible hypotube, a torque coupling assembly having a proximal end and a distal end, said torque coupling assembly being connected to said elongated flexible hypotube on said distal end thereof and to a high pressure, tubular, liquid supply line on said proximal end thereof and said elongated flexible hypotube extending from said torque coupling assembly to said proximal end of said torque handle, passing through said torque handle and extending externally from said distal end of said torque handle to said flexible tip section.

39. The infusion flow guidewire system of claim 38, wherein said guidewire further includes an elongated flexible delivery sheath surrounding said elongated flexible hypotube and extending internally from within said torque handle towards said flexible tip section, said elongated flexible delivery sheath being fixed near the proximal end of said torque handle.

40. The infusion flow guidewire system of claim 39, wherein said elongated flexible hypotube has a drawn-down section extending in a distal direction, a cylindrical reinforcement collar surrounding and fixed to a portion of said drawn-down section of said hypotube, a plurality of jet orifices in said drawn-down section and a plurality of jet orifices in said reinforcement collar in alignment with said jet orifices in said drawn-down section of said hypotube, said jet orifices in said reinforcement collar being angled to expel said pressurized liquid in a rearward direction.

41. The infusion flow guidewire system of claim 40, wherein said cylindrical reinforcement collar is fixed to said portion of said drawn-down section of said hypotube by a plurality of laser welds.

42. The infusion flow guidewire system of claim 40, wherein a flexible core wire is fixed within a distal portion of said drawn-down section of said hypotube and extends from said distal end thereof a predetermined distance terminating at a weld at a distal end of said flexible tip section.

43. The infusion flow guidewire system of claim 42, wherein said flexible core wire is cylindrically shaped for a major portion thereof and substantially flat the remainder thereof terminating in said weld.

44. The infusion flow guidewire system of claim 43, wherein said flexible core wire is made from gold-plated steel.

45. The infusion flow guidewire system of claim 43, wherein an elongated flexible coil surrounds a substantial portion of said drawn-down section of said hypotube and surrounds said extended portion of said flexible core wire and terminating in said weld.

46. The infusion flow guidewire system of claim 45, wherein said elongated flexible coil is attached to said drawn-down section of said flexible hypotube by soldering, welding or otherwise suitably attached.

47. The infusion flow guidewire system of claim 45, wherein said flexible coil is made from platinum.

48. The infusion flow guidewire system of claim 45, wherein said cylindrical reinforcement collar has a proximal end and a distal end and wherein said flexible coil has a proximal end and a distal end, said proximal end of said flexible coil being adjacent said distal end of said reinforcement collar and said distal end of said flexible coil terminating in said weld.

49. The infusion flow guidewire system of claim 45, wherein said elongated flexible hypotube and said elongated flexible delivery sheath, either separately or together, are secured within said torque handle such that they can be rotated or longitudinally moved in a distal or proximal direction.

50. The infusion flow guidewire system of claim 45, wherein said torque handle has a substantially tubular body with a proximal end and a distal end, said tubular body having external threads at said proximal end thereof, a collet with flexible jaws attached to said proximal end of said tubular body, a nut having internal threads therein for cooperating with said external threads of said tubular body to cause, when said nut and tubular body are twisted relative to each other, a horizontal movement between said tubular body and said nut resulting in the clamping or releasing of said elongated flexible hypotube between said jaws of said collet.

51. The infusion flow guidewire system of claim 50, wherein said tubular body has strain relief tube partially inserted and fixed within said distal end of said tubular body and extending externally a short distance beyond said distal end of said tubular body.

52. The infusion flow guidewire system of claim 50, wherein said torque coupling assembly has a stationary knob at its proximal end and a rotatable knob at its distal end, an internally threaded insert embedded in said rotatable knob, said stationary knob having a central bore therein with an internally threaded tubular insert partially fixed within said central bore, an elongated tubular member having an external thread along its entire length, said tubular member having a proximal end and a distal end, said external threads adjacent said proximal end of said tubular member engaging said internal threads of said internally threaded tubular insert of said stationary knob and said external threads adjacent said distal end of said tubular member engaging said internal threads of said internally threaded insert of said rotatable knob, said tubular member having a central bore therein which central bore opens at said distal end of said tubular member and terminates in a proximal direction at a surface wall within said tubular member, said tubular member having a tubular flange extending from said proximal end thereof, said tubular member having a smaller central bore therein which smaller central bore begins from said surface wall within said tubular member and extends through said tubular flange, an elongated compression tube being inserted within said central bore, said elongated compression tube having a proximal end and a distal end, said elongated compression tube having a central bore therethrough with a diameter slightly greater than the outer diameter of said elongated flexible hypotube passing therethrough, a partial bore being defined between said distal end of said elongated tubular member and an internal surface of said internally threaded insert of said stationary knob, a tubular collet sandwiched between said internal surface of said internally threaded surface of said stationary knob and an external surface at said distal end of said elongated compression tube, and said tubular collet having a plurality of flexible jaws and a plurality of arcuate surfaces interfacing an annual tapered surface at the distal end of said elongated compression tube.

53. The infusion flow guidewire system of claim 52, wherein said elongated compression tube has an annular recess at said proximal end thereof and a compressible O-ring inserted therein and interfacing said surface wall of said elongated tubular member.

54. The infusion flow guidewire system of claim 52, wherein said internally threaded tubular insert of said stationary knob has at least one threaded hole in its peripheral wall and an externally threaded set screw engaging said at least one threaded hole.

55. The infusion flow guidewire system of claim 40, wherein said elongated flexible hypotube and said cylindrical reinforcement collar are made of nitinol.

56. The infusion flow guidewire system of claim 45, wherein said elongated flexible coil is made of platinum.

57. The infusion flow guidewire system of claim 38, wherein the greater portion of said elongated flexible hypotube has an outer diameter of 0.014 inch and inner diameter of 0.010 inch.

58. The infusion flow guidewire system of claim 57, wherein said pressurized liquid is delivered to said elongated flexible hypotube at a pressure exceeding 0.25 kpsi at a flow rate of 5 cc/min.

59. The infusion flow guidewire system of claim 39, wherein said elongated flexible delivery sheath is made from braided polyimide.

60. The infusion flow guidewire system of claim 50, wherein said collet has a proximal end and a distal end, said collet having said flexible jaws at said proximal end and a tubular member extending from said flexible jaws, said elongated flexible delivery sheath being secured within said tubular member remote from said flexible jaws and near said distal end of said collet by an adhesive.

61. The infusion flow guidewire system of claim 39, whereby said torque handle includes means for simultaneously or individually rotating or longitudinally moving said elongated flexible hypotube and said elongated flexible delivery sheath.

62. The infusion flow guidewire system of claim 39, whereby said torque coupling assembly includes means for rotationally or longitudinally moving said elongated flexible hypotube.