Radio-frequency-based catheter system with improved deflection and steering mechanisms

• US 7,004,938 B2
• Filed: 11/27/2002
• Issued: 02/28/2006
• Est. Priority Date: 11/29/2001
• Status: Expired due to Term

• Current Assignee: MedWaves, Inc.
• Original Assignee: MedWaves, Inc.
• Inventors: Leung, George L., Ormsby, Theodore C., Law, Ming-Fan
• Primary Examiner(s): ROLLINS, ROSILAND STACIE
• Application Number:
  US10/306,757
• Publication Number:
  US 20030114844A1
• Time in Patent Office: 1,189 Days
• Field of Search: 606/41, 606 32- 34, 606/47, 606/129, 606/50, 606/4, 607/96, 607/101, 607/115, 607/116, 607/152, 607/154, 607/156, 607/100
• US Class Current: 606/33
• 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 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00839 Bioelectrical parameters, e.g. ECG, EEG
• CPC Class Codes: C08L 2201/12 Shape memory
• CPC Class Codes: H01Q 1/42 Housings not intimately mechanically associated with radiating elements, e.g. radome

Abstract

A RF catheter system includes a catheter with a proximal portion, a distal portion having a distal end and a lumen extending from the proximal portion to the distal portion. Inner and outer coaxially aligned conductors extend within the catheter and are coaxial with the lumen. A deflectable catheter guide is disposed within the catheter lumen and extends proximally within the catheter lumen and terminates distally of the distal end of the catheter to define a biological ablation pathway. A radio-frequency antenna is disposed at the distal portion of the catheter and is in electrical communication with the inner and outer coaxially aligned conductors. The radio-frequency antenna is adaptable to receive and transmit radio-frequency energy for ablating biological tissue along the ablation pathway.

Claims

1. A shapeable curvilinear radio-frequency antenna apparatus for ablating biological tissue within the body vessel of a patient, comprising:

a) a flexible catheter body including a distal portion and an elongated lumen;

b) inner and outer coaxially aligned, circumferentially spaced, longitudinally elongated conductors extending within the catheter and coaxial with the lumen;

c) a dielectrically enclosed flexible curvilinear radio-frequency antenna carried by the distal portion of the flexible catheter body in electrical communication with the inner and outer coaxially aligned conductors and adaptable to receive and transmit radio-frequency energy to apply a substantially consistently distributed electromagnetic field energy along the radio-frequency antenna for ablating biological tissue;

d) a pre-shaped deflection member carried by the flexible curvilinear radio-frequency antenna adaptable to take a pre-shaped memory curvilinear configuration;

e) a deflection regulating member operatively associated with the pre-shaped deflection member for regulating the deflection of said pre-shaped deflection member, wherein at least one of the pre-shaped deflection member and the deflection regulating member controllable for changing the configuration of the flexible curvilinear radio-frequency antenna between a straight configuration and a pre-shaped memory curvilinear configuration, wherein the deflection regulating member and the pre-shaped deflection member are relatively slidably with respect to each other in the elongated lumen.

2. The antenna apparatus of claim 1, wherein the pre-shaped deflection member is an elongated, flexible spine made of a shape-memory alloy and longitudinally disposed in the elongated lumen.

3. The antenna apparatus of claim 1, wherein the deflection regulating member is an elongated, rigid member longitudinally adjacent to the pre-shaped deflection member in the elongated lumen.

4. The antenna apparatus of claim 1, wherein the pre-shaped deflection member is movable for changing the configuration of the flexible curvilinear radio-frequency antenna between a straight configuration and a pre-shaped memory curvilinear configuration.

5. The antenna apparatus of claim 1, further including a deflection control mechanism coupled to at least one of the pre-shaped deflection member and the deflection regulating member for changing the configuration of the flexible curvilinear radio-frequency antenna between a straight configuration and a pre-shaped memory curvilinear configuration.

6. The antenna apparatus of claim 5, wherein the deflection control mechanism includes a movable control member that is rotatable to cause longitudinal movement of at least one of the pre-shaped deflection member and the deflection regulating member.

7. The antenna apparatus of claim 5, wherein the deflection control mechanism includes a movable control member that is movable in a linear direction to cause longitudinal movement of at least one of the pre-shaped deflection member and the deflection regulating member.

8. The antenna apparatus of claim 1, wherein the pre-shaped deflection member is incorporated into at least one of the catheter body and the flexible curvilinear radio-frequency antenna.

9. The antenna apparatus of claim 1, wherein the radio-frequency antenna is adaptable to receive and transmit microwave energy at a frequency greater than 300 Megahertz.

10. A method of ablating biological tissue within the body vessel of a patient, comprising the steps of:

a) providing a shapeable curvilinear radio-frequency antenna apparatus for ablating biological tissue within the body vessel of a patient, the shapeable curvilinear radio-frequency antenna apparatus including a flexible catheter body having a distal portion and an elongated lumen;

inner and outer coaxially aligned, circumferentially spaced, longitudinally elongated conductors extending within the catheter and coaxial with the lumen;

a dielectrically enclosed flexible curvilinear radio-frequency antenna carried by the distal portion of the flexible catheter body in electrical communication with the inner and outer coaxially aligned conductors and adaptable to receive and transmit radio-frequency energy to apply a substantially consistently distributed electromagnetic field energy along the radio-frequency antenna for ablating biological tissue;

a pre-shaped deflection member carried by the flexible curvilinear radio-frequency antenna adaptable to take a pre-shaped memory curvilinear configuration;

a deflection regulating member operatively associated with the pre-shaped deflection member for regulating the deflection of said pre-shaped deflection member, the deflection regulating member and the pre-shaped deflection member being relatively slidably with respect to each other in the elongated lumen;

b) delivering the shapeable curvilinear radio-frequency antenna apparatus to a targeted body tissue ablation site within the body vessel of a patient;

c) controlling at least one of the pre-shaped deflection member and the deflection regulating member by sliding at least one of the pre-shaped deflection member and the deflection regulating member relative to the other to change the configuration of the flexible curvilinear radio-frequency antenna from a straight configuration to a pre-shaped memory curvilinear configuration so that the flexible curvilinear radio-frequency antenna is adjacent to the body tissue to be ablated; and

d) ablating the body tissue using the flexible curvilinear radio-frequency antenna by applying a substantially consistently distributed electromagnetic field energy to the body tissue along the radio-frequency antenna.

11. The method of claim 10, wherein the pre-shaped deflection member is an elongated, flexible spine made of a shape-memory alloy and longitudinally disposed in the elongated lumen.

12. The method of claim 10, wherein the deflection regulating member is an elongated, rigid member longitudinally adjacent to the pre-shaped deflection member in the elongated lumen.

13. The method of claim 10, wherein controlling at least one of the pre-shaped deflection member and the deflection regulating member includes moving the pre-shaped deflection member for changing the configuration of the flexible curvilinear radio-frequency antenna from a straight configuration to a pre-shaped memory curvilinear configuration.

14. The method of claim 10, further including a deflection control mechanism coupled to at least one of the pre-shaped deflection member and the deflection regulating member for changing the configuration of the flexible curvilinear radio-frequency antenna from a straight configuration to a pre-shaped memory curvilinear configuration, and the method further includes using the deflection control mechanism to change the configuration of the flexible curvilinear radio-frequency antenna from a straight configuration to a pre-shaped memory curvilinear configuration.

15. The method of claim 14, wherein the deflection control mechanism includes a movable control member that is rotatable to cause longitudinal movement of at least one of the pre-shaped deflection member and the deflection regulating member.

16. The method of claim 14, wherein the deflection control mechanism includes a movable control member that is movable in a linear direction to cause longitudinal movement of at least one of the pre-shaped deflection member and the deflection regulating member.

17. The method of claim 10, wherein the pre-shaped deflection member is incorporated into at least one of the catheter body and the flexible curvilinear radio-frequency antenna.

18. The method of claim 10, wherein the radio-frequency antenna is adaptable to receive and transmit microwave energy at a frequency greater than 300 Megahertz.