Methods and apparatuses for remodeling tissue of or adjacent to a body passage

1. A catheter, comprising:

an elongate flexible catheter body; and

an expandable structure associated with the catheter body and including a radially expandable balloon and a plurality of flexible circuits extending along an outer surface of the balloon, each flexible circuit including at least one electrode and at least one temperature sensor;

wherein at least a portion of the outer surface of the balloon includes a flexible polyimide film;

wherein the flexible polyimide film defines a base insulative layer of the plurality of flexible circuits; and

wherein the expandable structure has an outer diameter of less than 4 mm when in an expanded configuration.

2. The catheter of claim 1 , wherein the outer diameter of the expandable structure is between approximately 1 mm and 3 mm.

3. The catheter of claim 1 , wherein the balloon is non-cannulated.

4. The catheter of claim 1 , wherein an upper surface of the base insulative layer of the balloon directly contacts a conductive layer of at least one of the flexible circuits.

5. The catheter of claim 1 , wherein each flexible circuit includes a base insulative layer adjacent the outer surface of the balloon.

6. A system for renal denervation of a patient having a primary renal artery extending between an aorta and a kidney and an accessory renal artery extending between the aorta and the kidney, the system comprising:

a first balloon catheter and a second balloon catheter, each having a balloon with a small profile configuration and a large profile configuration, with a plurality of flexible circuits extending along an outer surface of each balloon, each flexible circuit including at least one electrode, wherein at least one of the balloons has a large profile configuration that is less than 4 mm in outer diameter; and

a power source electrically coupled to the electrodes of the first and second balloon catheters and configured to energize the electrodes with a renal denervation energy.

7. The system of claim 6 , wherein one of the balloons has a large profile configuration that is equal to or greater than 4 mm in outer diameter.

8. The system of claim 6 , wherein the first and second balloons have large profile configurations that are different outer diameter sizes.

9. The system of claim 6 , wherein the system is for renal denervation of a patient further having a second renal artery extending between the aorta and a second kidney, the system further comprising a third balloon catheter having a small profile configuration and a large profile configuration, with a plurality of flexible circuits extending along an outer surface of the third balloon, each flexible circuit including at least one electrode; and wherein the electrodes of the third balloon catheter are electrically coupled to the power source.

10. The system of claim 9 , wherein the first, second and third balloons, when in the large profile configurations, define different outer diameters from one another.

11. The system of claim 10 , wherein the outer diameter of the third balloon when in the large profile configuration is greater than or equal to 4 mm.

12. A renal denervation method, comprising:

positioning a radially expandable structure of an elongate flexible catheter body at a location in an accessory renal artery connecting an aorta to a kidney, the aorta and the kidney further connected by a primary renal artery, the radially expandable structure comprising a plurality of electrodes;

expanding the radially expandable structure such that at least a subset of the electrodes engage a wall of the accessory renal artery;

using a power source electrically coupled to the electrodes, energizing at least a subset of the plurality of electrodes to deliver energy to tissue proximate the accessory renal artery.

13. The renal denervation method of claim 12 , further comprising positioning the radially expandable structure at a location in the primary renal artery, expanding the radially structure such that at least some of the electrodes engage a wall of the primary renal artery, and energizing at least some of the electrodes to deliver energy to tissue proximate the primary renal artery.

14. The renal denervation method of claim 12 , further comprising positioning a second radially expandable structure of a second elongate flexible catheter body at a location in the primary renal artery; expanding the second radially expandable structure such that at least a subset of a plurality of electrodes of the second radially expandable structure engage a wall of the primary renal artery; and energizing at least a subset of the electrodes of the second radially expandable structure to deliver energy to tissue proximate the primary renal artery.

15. The renal denervation method of claim 12 , wherein energizing the electrodes comprises a plurality of energization cycles, wherein the electrodes in the subset of energized electrodes varies between at least some of the energization cycles.

16. The renal denervation method of claim 15 , wherein an energy output setting of the power source varies between at least some of the energization cycles.

17. The renal denervation method of claim 12 , wherein the radially expandable structure has an outer diameter of less than 4 mm when in an expanded configuration.

18. The renal denervation method of claim 12 , wherein the radially expandable structure has an outer diameter of 1 mm to 3 mm when in an expanded configuration.