Steerable electrophysiology catheter

• US 5,545,200 A
• Filed: 11/22/1994
• Issued: 08/13/1996
• Est. Priority Date: 07/20/1993
• Status: Expired due to Term

• Current Assignee: Medtronic Cardiorhythm
• Original Assignee: Medtronic Cardiorhythm
• Inventors: Nguyen, Frank, West, Scott H.
• Primary Examiner(s): Green, Randall L.
• Assistant Examiner(s): VANOVER, PERRY
• Application Number:
  US08/343,310
• Time in Patent Office: 630 Days
• Field of Search: 607/122, 607/123, 607/116, 607/119, 604/95, 604/264, 604/265, 604/280, 606/33, 606/41, 606/29, 606/46, 606/48, 606/49, 606/50, 128/642, 128/668, 128/670, 128/695
• US Class Current: 607/122
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2018/00065 porous
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00392 Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61B 2018/0091 Handpieces of the surgical instrument or device
• CPC Class Codes: A61B 2018/00946 slidable
• CPC Class Codes: A61B 2018/00952 rotatable
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2018/1435 Spiral
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61M 2025/0063 having means, e.g. stylets, mandrils, rods or wires to reinforce or adjust temporarily the stiffness, column strength or pushability of catheters which are already inserted into the human body
• CPC Class Codes: A61M 2025/015 Details of the distal fixation of the movable mechanical means
• CPC Class Codes: A61M 2025/0161 wherein the distal tips have two or more deflection regions
• CPC Class Codes: A61M 25/0136 Handles therefor
• CPC Class Codes: A61M 25/0141 having flexible regions as a result of using materials with different mechanical properties
• CPC Class Codes: A61M 25/0144 having flexible regions as a result of inner reinforcement means, e.g. struts or rods
• CPC Class Codes: A61M 25/0147 : with movable mechanical means, e.g. pull wires
• CPC Class Codes: A61N 1/056 : Transvascular endocardial electrode systems

Abstract

An electrophysiology catheter (20) comprises a shaft (22) having a first bending stiffness and a deflectable tip (28) secured to the distal end (24) of the shaft with a second bending stiffness less than the first bending stiffness. At least one electrode (34, 36) is mounted to the tip for delivering current to or monitoring electrical activity of tissue. A manipulator wire (58) is coupled to the distal end of the deflectable tip, whereby the deflectable tip may be deflected by axial force applied to the manipulator wire. A stiffener member (66) is axially slidable relative to the tip so as to adjust the tip curvature without removing the catheter from the body. The catheter may further include a core wire (72) configured to rotate the deflectable tip about a longitudinal axis (2) without rotating the proximal end (26) of the catheter shaft, wherein the distal end of the deflectable tip remains in a substantially constant axial position, preferably in a plane perpendicular to the longitudinal axis.

Claims

1. A steerable electrophysiology catheter comprising:

a handle;

a shaft having a proximal end extending from the handle, a distal end, and an axial lumen therebetween;

a deflectable tip having a proximal end secured to the distal end of the shaft, a distal end and an axial tip lumen in communication with the axial lumen of the shaft;

at least one electrode secured to the deflectable tip;

an electrical current path between the handle and the electrode;

a core wire disposed in the axial lumen of the shaft and the tip lumen, the core wire having a distal end rotatably driveably coupled to the deflectable tip and a proximal end at the handle; and

the handle comprising a core wire rotator rotatively drivingly coupled to the proximal end of the core wire so to rotate the core wire about its axis thereby rotating the deflectable tip about a longitudinal axis without the need to rotate the proximal end of the shaft.

2. The catheter of claim 1 wherein the proximal end of the tip is secured to the core wire so to transmit torque from the core wire to the tip at the proximal end of the tip.

3. The catheter of claim 1 wherein the core wire is secured to the distal end of the tip so to transfer torque from the core wire to the distal end of the tip.

4. The catheter of claim 3 wherein the core wire has about the same bending stiffness about two perpendicular lines.

5. The catheter of claim 4 wherein the core wire has a circular cross-sectional shape.

6. The catheter of claim 1 wherein the core wire rotater includes a core wire drive element connected to the proximal end of the core wire and a core wire torquer ring rotatably coupled to the core wire drive element and rotatably mounted about the housing for manipulation by a user.

7. The catheter of claim 6 wherein the core wire drive element and the core wire torquer ring include mating gear teeth by which the core wire torquer ring rotates the core wire drive element and the proximal end of the core wire therewith.

8. The catheter of claim 6 wherein the core wire rotater includes:

a retainer surface adjacent to the core wire torquer ring; and

a spring washer mounted about the housing and captured between the retainer surface and the core wire torquer ring to create a frictional resistance to the rotation of the core wire torquer ring about the housing and to provide unlimited positional adjustment of said core wire torquer ring.

9. The catheter of claim 1 further comprising a tubular strain relief member acting as an interface between the shaft and the handle, the strain relief member having an inside surface and the shaft having an outside surface, the inside surface of the strain relief and the outside surface of the shaft made of heat weld compatible materials so the strain relief and the tube can be heat weldable to one another without the use of an adhesive.

10. The catheter of claim 1 wherein the core wire rotator includes means for rotatably drivingly engaging the proximal end of the core wire while permitting the proximal end of the core wire to move freely, relative to the handle, in an axial direction.

11. The catheter of claim 1 wherein the at least one electrode includes a tip electrode and a tip insulating connector securing the tip electrode to the shaft.

12. The catheter of claim 11 further comprising means for creating a mechanical/thermal bond between the shaft and the tip insulating connector, said bond creating means including openings formed in the tip insulating connector into which softened shaft material can flow.

13. The catheter of claim 11 wherein the tip insulating connector includes first and second bores within which the distal end of the core wire can be housed to rotatably driveably couple the deflectable tip to the core wire.

14. A steerable electrophysiology catheter comprising:

a handle;

a shaft with a first bending stiffness, the shaft having a proximal end extending from the handle, a distal end, and an axial lumen therebetween;

a deflectable tip with a second bending stiffness less than the first bending stiffness, the deflectable tip having a proximal end secured to the distal end of the shaft, a distal end and an axial tip lumen in communication with the axial lumen of the shaft;

at least one electrode secured to the deflectable tip;

an electrical current path between the handle and the electrode;

a manipulator wire extending through the axial lumen of the shaft and the tip lumen, the manipulator wire having a distal end secured to the deflectable tip and a proximal end at the handle;

an elongate, flexible stiffener element slidably disposed in the axial lumen of the shaft and the tip lumen, the stiffener element having a third bending stiffness;

a core wire disposed in the axial lumen of the shaft and the tip lumen, the core wire having a distal end rotatably driveably coupled to the deflectable tip and a proximal end at the handle; and

the handle comprising;

a housing;

a core wire rotater rotatively drivingly coupled to the proximal end of the core wire so to rotate the core wire about its axis thereby rotating the deflectable tip about a longitudinal axis without the need to rotate the proximal end of the shaft;

a manipulator wire driver axially drivingly coupled to the proximal end of the manipulator wire to apply an axial force to the manipulator wire to deflect the deflectable tip into a first curvature; and

a stiffener element driver axially drivingly coupled to the proximal end of the stiffener element to axially move the stiffener element relative to the deflectable tip such that at least a portion of the deflectable tip assumes a second curvature.

15. The catheter of claim 14 wherein the core wire is secured to the distal end of the tip so to transmit torque from the core wire to the tip at the distal end of the tip.

16. The catheter of claim 14 wherein the axial tip lumen of the deflectable tip comprises a first, radially offset, axial tip lumen housing the manipulator wire, a second axial tip lumen housing the stiffener element, and a third axial tip lumen housing the core wire.

17. The catheter of claim 16 wherein the stiffener element driver includes:

a second collet slide ring including;

an inner ring, coupled to the manipulator wire, having a radially deflectable arm, the inner ring mounted about the housing for axial movement along but not radial movement about the housing; and

an outer ring rotatably mounted over the inner ring, the inner and outer rings including tapered camming surface means for biasing the arm of the inner ring inwardly against the housing thereby frictionally securing the collet slide ring at a chosen axial position along the housing.

18. The catheter of claim 14 further comprising a tubular strain relief member acting as an interface between the shaft and the handle, the strain relief member having an inside surface and the shaft having an outside surface, the inside surface of the strain relief and the outside surface of the shaft made of heat weld compatible materials so the strain relief and the tube can be heat weldable to one another without the use of an adhesive.

19. A steerable electrophysiology catheter comprising:

a handle;

a shaft having a proximal end extending from the handle, a distal end, and an axial lumen therebetween;

a deflectable tip having a proximal end secured to the distal end of the shaft, a distal end and an axial tip lumen in communication with the axial lumen of the shaft;

at least one electrode secured to the deflectable tip;

an electrical current path between the handle and the electrode;

a manipulator wire extending through the axial lumen of the shaft and the tip lumen, the manipulator wire having a distal end secured to the distal end of the deflectable tip and a proximal end at the handle; and

the handle comprising a manipulator wire driver axially drivingly coupled to the proximal end of the manipulator wire to apply an axial force to the manipulator wire to deflect the deflectable tip into a first curvature; and

a tubular strain relief member acting as an interface between the shaft and the handle, the strain relief member having an inside surface and the shaft having an outside surface, the inside surface of the strain relief and the outside surface of the shaft made of heat weld compatible materials so the strain relief and the tube can be heat weldable to one another without the use of an adhesive.

20. A steerable electrophysiology catheter comprising:

a handle;

a shaft having a proximal end extending from the handle, a distal end, and an axial lumen therebetween;

a deflectable tip having a proximal end secured to the distal end of the shaft, a distal end and an axial tip lumen in communication with the axial lumen of the shaft;

at least one electrode secured to the deflectable tip;

an electrical current path between the handle and the electrode;

a manipulator wire extending through the axial lumen of the shaft and the tip lumen, the manipulator wire having a distal end secured to the distal end of the deflectable tip and a proximal end at the handle; and

a manipulator wire driver mounted to the handle and axially drivingly coupled to the proximal end of the manipulator wire to apply an axial force to the manipulator wire to deflect the deflectable tip into a first curvature; and

said manipulator wire driver including a first, axially movable element secured to the manipulator wire, a second element rotatably mounted to the first element and cam means for biasing a chosen one of the first and second elements against the handle so to secure the manipulator wire driver at a chosen axial position according to the rotary orientation of the second element.

21. The catheter of claim 20 wherein the second element is said chosen one of the first and second elements.

22. The catheter of claim 21 wherein said first element is a ring-like element having at least one weakened region to permit a part of the first element to be biased against the handle by the second element.

23. A steerable electrophysiology catheter comprising:

a handle;

a shaft with a first bending stiffness, the shaft having a proximal end extending from the handle, a distal end, and an axial lumen therebetween;

a deflectable tip with a second bending stiffness less than the first bending stiffness, the deflectable tip having a proximal end secured to the distal end of the shaft, a distal end and an axial tip lumen in communication with the axial lumen of the shaft;

at least one electrode secured to the deflectable tip;

an electrical current path between the handle and the electrode;

a manipulator wire extending through the axial lumen of the shaft and the tip lumen, the manipulator wire having a distal end secured to the deflectable tip and a proximal end at the handle;

a core wire disposed in the axial lumen of the shaft and the tip lumen, the core wire having a distal end rotatably driveably coupled to the deflectable tip and a proximal end at the handle; and

the handle comprising;

a housing;

a core wire rotater rotatively drivingly coupled to the proximal end of the core wire so to rotate the core wire about its axis thereby rotating the deflectable tip about a longitudinal axis without the need to rotate the proximal end of the shaft; and

a manipulator wire driver axially drivingly coupled to the proximal end of the manipulator wire to apply an axial force to the manipulator wire to deflect the deflectable tip into a first curvature.

24. The catheter of claim 23 wherein the core wire is secured to the distal end of the tip so to transmit torque from the core wire to the tip at the distal end of the tip.

25. The catheter of claim 24 wherein the core wire has about the same bending stiffness about two perpendicular lines whereby torque transmitted to the tip by the core wire causes the tip to move along a path which defines other than a plane perpendicular to axial lumen of the shaft.

26. The catheter of claim 25 wherein the core wire has a circular cross-sectional shape.

27. The catheter of claim 23 wherein the core wire rotator includes means for rotatably drivingly engaging the proximal end of the core wire while permitting the proximal end of the core wire to move freely, relative to the handle, in an axial direction.

28. The catheter of claim 23 wherein the manipulator wire driver is adapted to push and pull the manipulator wire.

29. The catheter of claim 23 wherein the core wire rotater includes a core wire drive element connected to the proximal end of the core wire and a core wire torquer ring rotatably coupled to the core wire drive element and rotatably mounted about the housing for manipulation by a user.

30. The catheter of claim 29 wherein the core wire rotater includes:

a retainer surface adjacent to the core wire torquer ring; and

a spring washer mounted about the housing and captured between the retainer ring and the core wire torquer ring to create a frictional resistance to the rotation of the core wire torquer ring about the housing and to provide unlimited positional adjustment of said core wire torquer ring.

31. The catheter of claim 23 wherein the manipulator wire driver includes:

a collet slide ring including;

an inner ring, coupled to the manipulator wire, having a radially deflectable arm, the inner ring mounted about the housing for axial movement along but not radial movement about the housing; and

an outer ring rotatably mounted over the inner ring, the inner and outer rings including tapered camming surface means for biasing the arm of the inner ring inwardly against the housing thereby frictionally securing the collet slide ring at a chosen axial position along the housing.

32. A steerable electrophysiology catheter comprising:

a handle;

a shaft with a first bending stiffness, the shaft having a proximal end extending from the handle, a distal end, and an axial lumen therebetween;

a deflectable tip with a second bending stiffness less than the first bending stiffness, the deflectable tip having a proximal end secured to the distal end of the shaft, a distal end and an axial tip lumen in communication with the axial lumen of the shaft;

at least one electrode secured to the deflectable tip;

an electrical current path between the handle and the electrode;

a manipulator wire extending through the axial lumen of the shaft and the tip lumen, the manipulator wire having a distal end secured to the deflectable tip and a proximal end at the handle;

an elongate, flexible stiffener element slidably disposed in the axial lumen of the shaft and the tip lumen, the stiffener element having a third bending stiffness; and

the handle comprising;

a housing;

a manipulator wire driver axially drivingly coupled to the proximal end of the manipulator wire to apply an axial force to the manipulator wire to deflect the deflectable tip into a first curvature; and

means for securing the proximal end of the stiffener element to the handle at a chosen location whereby the curvature of the deflectable tip corresponds the chosen location.