Electrophysiology/ablation catheter having lariat configuration of variable radius

• US 20040034348A1
• Filed: 05/13/2003
• Published: 02/19/2004
• Est. Priority Date: 11/29/2000
• Status: Active Grant

• Current Assignee: St. Jude Medical (Abbott Laboratories Incorporated)
• Original Assignee: St. Jude Medical, Daig Division, Inc.
• Inventors: Rashidi, Rassoll
• Granted Patent: US 7,081,114 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• 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 2017/00243 cardiac
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2018/00184 Moving parts
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00577 Ablation

Abstract

A remotely deflectable electrophysiology/ablation catheter of the type intended for placing into an interior passage of the heart is disclosed. The distal end of this elongated tubular catheter has a pair of tension/compression members each with a flattened end portion connected to the distal electrode and extending through the catheter casing and attached to a user moveable actuator for effecting the tension/compression thereon for remotely curling the distal end of the catheter. Spaced ring electrodes are provided adjacent the distal electrode. A permanent bend is pre-formed in the casing and tension/compression members adjacent the ring electrodes about an axis perpendicular to the elongated tension/compression members. Movement of the remote actuator causes the distal portion of the catheter to curl into a lariat in a plane perpendicular to the axis along the elongated catheter casing, thus permitting electrical mapping or ablation with the distal and/or ring electrodes about the inner surface of the heart passage into which the lariat is formed and situated. The lariat can achieve a curvature greater than 360 degrees and at a significantly reduced radius to allow insertion of the catheter distal end into passages of reduced dimension.

Claims

1. An electrophysiology/ablation catheter comprising:

a) an elongated flexible tubular casing having a proximal end and at least one electrode disposed at a distal end thereof;

b) a catheter deflection assembly disposed in said casing;

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

d) an actuator connected to the proximal end of the catheter deflection assembly and operable upon movement to effect lateral displacement of the distal end in a curvature greater than 360 degrees.

2. The catheter defined in claim 1, wherein the catheter deflection assembly includes a pair of tension/compression members extending through said casing.

3. The catheter defined in claim 2, wherein the catheter deflection assembly moves the distal end in a plane substantially normal to a longitudinal extent of the catheter.

4. The catheter defined in claim 2, wherein tensioning of one of said pairs of tension/compression members and simultaneously compressing the other of the tension/compression members deflects the catheter.

5. The catheter defined in claim 2 wherein the tension/compression members are disposed in side-by-side relationship.

6. The catheter defined in claim 2, wherein said pair of tension/compression members each have a portion thereof adjacent said distal end formed to have a flattened transverse section with the balance thereof circular.

7. The catheter defined in claim 2, wherein said pair of tension/compression members each have a first portion thereof adjacent said distal end formed to have a flattened transverse section, and second portion located in the region of said bend have circular cross-section oriented substantially at right angle to said fixed portion with the balance thereof circular.

8. The catheter defined in claim 2, wherein said tension/compression members have a transversely resilient spacer disposed there between in the distal portion thereof.

9. The catheter defined in claim 1, wherein said lateral displacement comprises a curvature having a radius as small as five multiples of the transverse dimensions of said casing.

10. A method of disposing an electrophysiology/ablation catheter in an associated body cavity comprising the steps of:

a) providing an elongated tubular catheter and disposing at least one electrode on a distal end thereof;

b) disposing a pair of tension/compression members in the tubular catheter adjacent to the distal end and extending the members to adjacent a proximal end of said catheter;

c) connecting an actuator to the tension compression members adjacent the proximal end of the catheter;

d) moving the actuator and tensioning one of the tension/compression members and simultaneously compressing the other of the pair and curling the distal end of the tubular catheter in a lariat having a curvature greater than 360 degrees; and

, e) disposing the lariat in the associated body cavity to orient the electrodes in a circumferential direction about the inner periphery of the associated body cavity.

11. The method defined in claim 10, comprising the further step of opening the lariat after the lariat disposing step.

12. The method defined in claim 10 wherein the lariat curving step includes curving the distal end of the tubular catheter in a radius of curvature as small as five multiples of the transverse dimensions of the tubular catheter.

13. The method defined in claim 10 wherein the distal end curling step includes reducing a curvature of the distal end to a radius R_v.

14. The method defined in claim 13 comprising the further step of opening the lariat after the lariat disposing step to a final curvature of radius R_f greater than R_v.

15. The method defined in claim 14 wherein the distal end of the catheter has an initial curvature of radius R_i greater than R_v.

16. The method defined in claim 10 wherein the distal end of the catheter has an initial curvature of radius R_i and the distal end curling step includes reducing a curvature of the distal end to a radius R_v less than R_i.

17. The method defined in claim 10 wherein the distal end curling step includes forming the lariat in a plane substantially at a right angle to a direction of elongation of the tubular catheter.

18. A method of mapping/ablating an associated pulmonary vein/artery in a heart comprising the steps of:

a) providing a catheter having a plurality of spaced electrodes disposed on a distal end thereof;

b) inserting the distal end of the catheter in one of the associated vein/artery in the heart;

c) curling the catheter in the heart normal to the direction of elongation of the catheter and forming a lariat having a curvature of radius R_v; and

d) opening the lariat to a curvature having a radius R_f to orient the electrodes circumferentially about the inner periphery of the associated vein/artery.

19. The method defined in claim 18, wherein the step of inserting includes forming a pre-formed bend in the catheter having a curvature of radius R_i.

20. The method defined in claim 19, wherein the step of curling includes curling in a plane normal to the pre-formed bend.