Electrophysiology catheter and remote actuator therefor

• US 5,861,024 A
• Filed: 06/20/1997
• Issued: 01/19/1999
• Est. Priority Date: 06/20/1997
• Status: Expired due to Term

• Current Assignee: St. Jude Medical (Abbott Laboratories Incorporated)
• Original Assignee: Cardiac Assist Devices, Inc.
• Inventors: Rashidi, Rassoll
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): SCHAETZLE, KENNEDY
• Application Number:
  US08/880,080
• Time in Patent Office: 578 Days
• Field of Search: 600/373, 600/374, 600/380, 600/585, 600/114, 600/131, 600/146, 600/147, 600/149, 607/116, 607/119, 607/122, 607/133, 607/98, 607/99, 606/129, 604/280
• 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 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: A61N 1/0565 Electrode heads

Abstract

A cardiac catheter employed for minimally invasive cardiac diagnostic electrophysiology and/or cardiac ablation procedures. The catheter of this invention comprises of an elongated cylindrical and electrically non conductive main exterior tube with plurality of surface electrodes disposed on its distal portion, and a handle on its proximal end. The distal portion of this catheter can be curved and the assumed curvature can be retained by a single action on manual actuator of the catheter handle. In one embodiment of this invention an electromechanical drive system is incorporated into the catheter handle for formation of curvatures at the distal portion of the catheter. In a further embodiment an electrical heating element is incorporated within the distal electrode of the catheter for ablation procedures. In another embodiment of this invention a readily removable and disposable blood contacting segment is provided. The non-blood contacting actuator is thus reusable and reduces the cost of the cardiac electrophysiology and/or ablation procedure. The catheter of this invention comprises two tension/compression members for curvature formation at the distal end of the catheter. These tension/compression or pull/push members are wires with circular cross-sections that are integrally formed into ribbon-like configurations at their distal portions for enhanced deflectability. The actuator handle includes a pivoted member movable in one direction by the thumb of the user'"'"'s hand grasping the handle and in the opposite direction by the other fingers of the same hand.

Claims

1. An electrophysiology catheter comprising:

a) an elongated flexible hollow tubular housing having a proximal and distal end and a plurality of spaced electrodes disposed at the distal end thereof;

b) a pair of flexible tension/compression members disposed in side-by-side relationship and extending in the hollow of said housing from a point of attachment adjacent to said distal end to said proximal end of said tubular housing,

c) an electrical lead connected to each of said electrodes and extending through the hollow of said tubular housing to the proximal end thereof, said lead adopted for external connection thereto; and

,

d) wherein longitudinal tensioning of one of said tension/compression members with respect to said housing affects lateral displacement of said distal end of said housing in one direction and longitudinal tensioning of the other of said tension/compression member with respect to said housing affects lateral displacement of said distal end of said housing in a direction opposite said one direction.

2. The catheter defined in claim 1, wherein said tension/compression members have a generally circular cross-section with integrally flattened ribbon-like distal portion.

3. The catheter defined in claim 1, wherein said tension/compression members have a constant circular and rectangular configurations in transverse sections.

4. The catheter defined in claim 1, wherein one of said electrodes is disposed at the distal end of said tubular housing.

5. The catheter defined in claim 1 further comprising:

a helically wound wire disposed in the hollow of said tubular housing with said pair of tension/compression members disposed within said helically wound wire.

6. The catheter defined in claim 1 further comprising a coiled wire extending within said housing from said distal end to said proximal end, with a predetermined section of the length of said coil proximate said distal end formed of open winding, with the balance of side coil formed with closed windings.

7. The catheter defined in claim 1, further comprising:

a) a helically wound member disposed in the hollow of said housing with said pair of tension/compression members disposed within said helically wound member;

b) actuator structure including (i) a rigid body member attached to the proximal end of said housing and having the proximal end of said helically wound member registered against said body member, (ii) a control member pivotally mounted on said body member and having the proximal ends of said tension/compression members connected thereto respectively on opposite sides of said pivotal mount; and

,

c) Wherein user movement of said control member in one direction tensions one of said tension/compression members affecting said axial movement and tends to compress the other tension/compression member and user movement of said control member in a direction opposite said one direction applies tension to the other of said tension/compression members affecting said longitudinal movement and tends to compress said one tension/compression member.

8. The catheter defined in claim 1, wherein said housing has stiffening structure disposed in said hollow for resisting said torsional distortion for a predetermined longitudinal portion thereof extending from said proximal end.

9. The catheter defined in claim 1, further comprising:

a) stiffening structure disposed in said hollow housing and operative for preventing said torsional distortion for a predetermined proximal portion thereof;

b) actuator structure including;

(i) a body attached to the proximal end of said housing;

(ii) a user movable control member pivotally disposed on said body, (iii) a pair of sliders movably disposed on said body, each of said sliders having the proximal end of one of said tension/compression members connected thereto;

(iv) a pair of connector links each having an end thereof connected to one of said sliders and the end remote therefrom pivotally connected to said control member respectively on opposite sides of said;

pivot; and

c) wherein user pivotal movement of said control member in one direction affects movement of one of said sliders in a direction such that said one slider tensions one of said tension/compression members and the other of said sliders is moved in a direction toward said proximal end and tends to longitudinally compress the other of said tension/compression members, and wherein user pivotal movement of said control member in a direction opposite said one direction affects movement of the other of said sliders in a direction such that the other of said tension/compression members is tensioned and said one slider is moved in a direction toward said proximal end and tends to longitudinally compress said one tension/compression member.

10. A catheter comprising:

a) an elongated flexible tubular casing having a distal end and a proximal end;

b) a flexible generally tubular member received in said casing in relatively closely fitting arrangement, said tubular member extending from said distal end to said proximal end;

c) a first and second tension/compression members each having a generally circular cross-section with integrally flattened ribbon-like distal portion and disposed in said tubular member in face-to-face contacting sliding parallel arrangement with an end of each secured to said tubular member at the distal end thereof, said first and second tension/compression members extending through said tubular member to the proximal end thereof; and

,

d) base structure attached to the proximal end of said tubular member and including a user-movable control member thereon;

said control member having a neutral position and a first actuated position on one side of said control member neutral position and a second actuated position on a side of said neutral position opposite said one side and operatively connected to said tension/compression members such that movement of said control member to said first position affects tensioning of said first tension/compression member and produces bending or curving of the distal portions of said casing and tubular member generally in a plane in one direction, with the remainder thereof remaining generally unbent, and movement of said control member to said second position produces tensioning of said second tension/compression member and bending or curving of the distal portion of said casing in said plane in a direction opposite said one direction, and movement of said control member to the neutral position from either of said first and second positions returns said casing and tubular member to an unbent generally straight condition.

11. The catheter defined in claim 10, wherein said tubular guide member is formed of helically coiled wire.

12. The catheter defined in claim 10, wherein said tubular guide member is formed of helically coiled wire with the distal portion of said tubular guide member structure comprising an open or spaced-coil region of said coiled wire and the remainder of said tubular guide member structure comprising a closed or stacked portion of said wire.

13. The catheter defined in claim 10, wherein said control member includes a member rotatable on side base structure.

14. The catheter defined in claim 10, wherein said control member includes pivoted links connected to each of said first and second tension/compression members.

15. The catheter defined in claim 10, wherein said distal end of said casing includes at least one electrode isolated from said tubular member, with an electrical lead connected to said electrode and extending from said electrodes to the proximal end of each casing and adopted for external connection thereto.

16. The catheter defined in claim 10 wherein said casing has a plurality of spaced electrodes disposed thereon and isolated from said tubular member with each of said electrodes having an electrical lead connected thereto with each of said leads extending along said casing to the distal end thereof, said leads adopted for external connection thereto.

17. A partially disposable electrophysiology catheter comprising:

a) a flexible tubular casing sub-assembly adapted for blood contacting usage having a distal end with a plurality of electrodes thereon;

said sub-assembly including an electrical and structural connection provided on a proximal end remote from said distal end;

b) a plurality of electrical leads disposed within said casing with each lead extending from one of said distal end electrodes to a discrete terminal on said electrical connection on said proximal end;

c) an actuator sub-assembly for non-blood contacting usage including an elongated flexible actuator member with a distal end insertable into said flexible casing, said actuator including a proximal end thereof having a handle with a user movable member thereon, said member operable upon user movement for affecting relative flexing of said distal end of said casing; and

,

d) electrical terminals on said handle for making releasable electrical connection to said discrete terminals on said proximal end of said casing, wherein said casing sub-assembly is removable from said actuator sub-assembly; and

said actuator sub-assembly is re-useable and said casing sub-assembly is disposable.

18. The catheter defined in claim 17, wherein said actuator includes a pair of tension/compression members having an end each attached to the distal end of said actuator, said tension/compression members extending to said handle and operatingly connected for pulling/pushing individually by said movement of said user movable member.

19. An electrophysiology/ablation catheter assembly comprising:

a) an elongated flexible tubular member having a distal end for blood contacting in vivo usage and a proximal end for connection to an actuator mechanism, said distal end having at least one exterior electrode with an electrical lead attached thereto and extending through said tubular member to said proximal end;

b) a pair of tension/compression members extending from said distal end of said tubular member therethrough to said proximal end;

c) a handle connected to said tubular member and having a user controllable actuator member pivotally and transversely mounted thereon, said actuator member having said pair of tension/compression members connected thereto for alternate pulling/pushing thereby, wherein upon the user grasping said handle with one hand and movement of said actuator member in one direction generally transverse to said handle by pushing thereon with the thumb of said one hand one of said pair of tension/compression members is tensioned, and upon gripping said actuator with at least one other finger of said hand, said actuator member is moved in a transverse direction opposite said one direction the other of said pair of tension/compression member is tensioned.

20. The catheter assembly defined in claim 19, wherein said actuator member is pivotally and transversely mounted on said handle.

21. The catheter assembly defined in claim 19, wherein said actuator member is pivotally mounted for movement in a slot through said handle.

22. The catheter assembly defined in claim 19, wherein said actuator member is pivotally mounted for movement in a slot through said handle with first position of said actuator extending on one side of said slot and a second position extending on the other side of said slot opposite said one side.

23. A method of operating an electrophysiology/ablation catheter comprising:

a) disposing at least one electrode on a distal portion of an elongated flexible tube and connecting an electrode lead to said electrode and extending said electrode to a proximal end of said tube;

b) disposing a pair of elongated tension/compression members in said tube and fixing an end of each of said pair in the distal portion of said tube and extending said pair to the proximal end of said tube;

c) connecting said tube to a handle and disposing an actuator member movably on said handle;

d) connecting an end of one of said pair of tension/compression members to opposite sides of said actuator; and

,

e) grasping said handle with one user'"'"'s hand and moving said actuator in one direction with the thumb of the user'"'"'s aforesaid hand, and affecting pulling of one of said pair and compression of the other of said pair, and moving said actuator in a direction opposite said one direction with at least one of the other fingers of said hand and affecting pulling of said other of said pair and compression of said one of said pair and thereby affecting deflection of said at least one electrode in a lateral direction with respect to said tube.

24. The method defined in claim 23, wherein said steps of disposing an actuator member on said handle includes pivotally mounting said actuator member on said handle.

25. The method defined in claim 23, wherein said steps of disposing said actuator member includes forming a slot through said handle and transversely pivoting said actuator for movement in said slot.

26. An electrophysiology catheter assembly comprising:

a) an elongated flexible tubular blood contacting member having at least one electrode provided in a distal end region thereof with an electrical lead connected to said electrode and extending through said tubular member to a proximal end thereof;

b) an inner non-blood contacting flexible sleeve member disposed in closely fitting arrangement in said tubular blood contacting member and extending from said proximal end to said distal end region;

c) a pair of elongated tension/compression members disposed in said inner sleeve, said pair having end portions thereof extending externally of said sleeve member into said distal region of said tubular member, said end portions having a flattened ribbon-like configurations and the remainder of said tension members having a non flattened wire configurations and extending to a proximal end of said tubular member;

d) a handle connected to the proximal end of said sleeve; and

,

e) an actuator mechanism associated with said handle including an actuator member user moveable in opposite directions for alternately tensioning first one and then the other of said tension/compression members.

27. The assembly defined in claim 26, wherein said pair of flattened ribbon-like portions of said tension/compression members are fixed together at a predetermined distance from said distal ends thereof.

28. The assembly defined in claim 26, wherein said pair of flattened ribbon-like portions of said tension/compression members pass freely through a guide bushing that torsionally constrains the flattened regions and allows axil movements of the said tension/compression members.

29. The assembly defined in claim 26, wherein said pair of flattened ribbon-like portions of said tension/compression members are fixed together by weldment in an annular member that serves as a kinematic junction, wherein the remaining distal portion of the catheter is un-deformed.