Apparatus and methods of use for treating blood vessels

1. An electrosurgical apparatus, comprising:

a cannula;

a microwave antenna including a distal end having a radiating section movably disposed within the cannula and positionable within a patient adjacent abnormal tissue, the microwave antenna adapted to connect to a source of electrosurgical energy for transmitting electrosurgical energy to the radiating section to both treat tissue and to transition the radiating section from a first state having a longitudinal configuration to a second state having a looped configuration; and

a sensor associated with the radiating section configured to monitor an electrical control parameter associated with the radiating section, the electrical control parameter selected from the group consisting of impedance, power, current, and voltage,

wherein the radiating section is configured to remain in the first state while positioned adjacent abnormal tissue until the electrosurgical energy is transmitted to the radiating section to controllably transition the radiating section to the second state.

2. An electrosurgical apparatus according to claim 1 , wherein at least a portion of the radiating section includes a cross-section area having a configuration selected from the group consisting of circular, flat and oval.

3. An electrosurgical apparatus according to claim 1 , wherein the microwave antenna is percutaneously positionable within a patient adjacent abnormal tissue.

4. An electrosurgical apparatus according to claim 3 , wherein at least one of the cannula or the microwave antenna is in operable communication with an image guidance device selected from the group consisting of an ultrasound device, an x-ray device, a fluoroscopy device, a cat scan device, a computer tomography (CT) device and a magnetic resonance imaging (MRI) device.

5. An electrosurgical apparatus according to claim 1 , wherein the radiating section is formed from a shape memory alloy.

6. An electrosurgical apparatus according to claim 5 , wherein the shape memory alloy is Nitinol.

7. An electrosurgical apparatus according to claim 5 , wherein the shape memory alloy is cold forged to form a radiating loop section that provides a closure pressure about tissue that ranges from 3 kg/cm 2 to 16 kg/cm 2 .

8. An electrosurgical apparatus according to claim 1 , wherein the radiating section is positionable adjacent abnormal tissue selected from the group consisting of aneurysms, fistulas and non-functional valves.

9. A method for treating various abnormalities associated with blood vessels, comprising:

inserting a microwave antenna including a radiating section into a cannula, the microwave antenna adapted to connect to a source of electrosurgical energy for transmitting electrosurgical energy to at least a portion of the radiating section;

transmitting electrosurgical energy to the radiating section to both treat abnormal tissue and to transition the radiating section from a first state having a longitudinal configuration to a second state having a looped configuration to encompass abnormal tissue adjacent the radiating section, the radiating section remaining in the first state while positioned adjacent abnormal tissue until the electrosurgical energy is transmitted to the radiating section to controllably transition the radiating section to the second state;

sensing an electrical control parameter associated with the radiating section selected from the group consisting of impedance, power, current, and voltage; and

triggering a control signal to the source of electrosurgical energy.

10. A method according to claim 9 , further comprising applying uniform pressure to abnormal tissue adjacent the radiating section.

11. A method according to claim 9 , further including severing at least a portion of the treated tissue.

12. A method according to claim 9 , wherein transmitting electrosurgical energy includes transmitting microwave energy.