Ablation catheter

1. A medical device, comprising:

an elongate body defining a lumen therethrough;

a shaft extending through the lumen; and

an electrode array coupled to an inner surface of the lumen of the elongate body at a first end and coupled to the shaft at a second end, the shaft being slidingly disposed within the lumen alongside at least a portion of the electrode array, wherein linear manipulation of the shaft causes the electrode array to transition from a first geometric configuration to a second configuration, and wherein rotational manipulation of the shaft causes the electrode array to transition from the second geometric configuration to a third configuration.

2. The medical device according to claim 1 , further comprising a linear actuator coupled to the shaft for the linear manipulation thereof.

3. The medical device according to claim 2 , further comprising a rotational actuator coupled to the shaft for the rotational manipulation thereof.

4. The medical device according to claim 1 , wherein the electrode array includes a plurality of electrodes, and wherein at least one of the plurality of electrodes defines a non-circular cross section.

5. The medical device according to claim 1 , wherein the first geometric configuration is a substantially linear configuration, the second geometric configuration includes one of a helical or circular configuration defining a first diameter, and the third geometric configuration includes one of a helical or circular configuration defining a second diameter greater than the first diameter.

6. The medical device according to claim 1 , wherein the first geometric configuration is a substantially linear configuration, the second geometric configuration includes one of a helical or circular configuration defining a first diameter, and the third geometric configuration includes one of a helical or circular configuration defining a second diameter less than the first diameter.

7. The medical device according to claim 1 , further comprising:

an electrocardiograph unit in electrical communication with the electrode array; and

a radiofrequency signal generator in electrical communication with the electrode array.

8. An intravascular catheter, comprising:

a catheter body defining a proximal portion and a distal portion;

a shaft extending from the distal portion of the catheter body;

a carrier arm coupled to an inner surface of the catheter body, the carrier arm being transitionable from a substantially linear configuration to a substantially helical configuration;

a distal tip defining a first lumen and a second lumen, wherein a portion of the shaft is disposed within the first lumen and a portion of the carrier arm is disposed within the second lumen; and

an electrode array disposed on the carrier arm.

9. The intravascular catheter according to claim 8 , further comprising a handle assembly coupled to the proximal portion of the catheter body.

10. The intravascular catheter according to claim 9 , wherein the handle assembly includes a linear actuator coupled to the shaft for the longitudinal movement thereof.

11. The intravascular catheter according to claim 10 , wherein the linear actuator element is releasably securable in a plurality of discrete positions on the handle assembly.

12. The intravascular catheter according to claim 9 , wherein the handle assembly includes a rotational actuator coupled to the shaft for the rotation thereof.

13. The intravascular catheter according to claim 12 , wherein the rotational actuator element is releasably securable in a plurality of discrete positions on the handle assembly.

14. The intravascular catheter according to claim 8 , wherein the electrode array includes a plurality of electrodes, and wherein at least one of the plurality of electrodes defines a non-circular cross section.

15. A method for ablating a tissue region, comprising:

positioning a treatment assembly of a medical device proximate a tissue region, the treatment assembly containing an electrode array having a first end coupled to an internal surface of a catheter body, and a second end coupled to a shaft extending from the catheter body and slidingly disposed within the catheter body alongside the first end of the electrode array;

manipulating the shaft in a linear direction to controllably transition the electrode array from a first geometric configuration to a second geometric configuration;

manipulating the shaft in a rotational direction to controllably transition the electrode array from the second geometric configuration to a third geometric configuration; and

delivering ablative energy to the treatment assembly.

16. The method according to claim 15 , wherein the first geometric configuration is a substantially linear configuration.

17. The method according to claim 16 , wherein the second geometric configuration includes one of a helical or circular configuration defining a first diameter.

18. The method according to claim 17 , wherein the third geometric configuration includes one of a helical or circular configuration defining a second diameter greater than the first diameter.

19. The method according to claim 17 , wherein the third geometric configuration includes one of a helical or circular configuration defining a second diameter less than the first diameter.

20. The method according to claim 17 , wherein manipulating the shaft in a rotational direction to controllably transition the electrode array from the second geometric configuration to a third geometric configuration includes manipulating the shaft in a first rotational direction to obtain a third geometric configuration defining a second diameter greater than the first diameter, and manipulating the shaft in a second rotational direction to obtain a third geometric configuration defining a second diameter less than the first diameter.