Methods and systems for controlling energy delivery in medical devices

1. A system for controlling an ablation procedure, comprising:

a user interface comprising a display; and

a memory with a computer executable method stored thereon, the computer executable method adapted to cause to be displayed on the display a power interface and a plurality of graphical elements, each graphical element of the plurality of graphical elements representing a corresponding electrode carried by an ablation catheter in communication with an ablation energy generator, the computer executable method further adapted to, in response to user interaction with the display in a manner specific to one of the plurality of graphical elements, toggle the respective plurality of graphical elements between at least three visual indicators respectively representing an active source state having an active source visual indicator, an active sink state having an active sink visual indicator, and an inactive state with an inactive state visual indicator, wherein each of the three visual indicators are unique,

wherein the active source state designates that the respective electrode is one of a plurality of active source electrodes, wherein the active sink state designates that the respective electrode is one of a plurality of active sink electrodes, wherein the plurality of active source electrodes together create a first pole in a bipolar mode, and wherein the plurality of active sink electrodes together create a second pole in the bipolar mode,

wherein the system is adapted to connect the plurality of active sink electrodes to a ground, and to connect the plurality of active source electrodes to a source,

wherein each active source electrode of the plurality of active source electrodes is adapted to be individually adjusted at a distinct power level using the power interface displayed on the display,

wherein an energy density at each of the plurality of active sink electrodes is different from an energy density at each of the plurality of active source electrodes,

wherein an energy density at each of the plurality of active sink electrodes is no more than 20% less than an energy density at each of the plurality of active source electrodes.

2. The system of claim 1 wherein the difference in energy densities is due to a difference in the number of active sink electrodes and the active source electrodes.

3. The system of claim 1 , wherein the computer executable method is further adapted to, in response to user interaction with the display in a manner specific to one of the plurality of graphical elements, toggle the respective plurality of graphical elements between a selected state with a selected state visual indicator, wherein the selected state visual indicator is different than the active source visual indicator, the active sink visual indicator, and the inactive state visual indicator.

4. The system of claim 1 , wherein the computer executable method is further adapted to calculate impedance associated with each of the active source electrodes and each of the active sink electrodes and tissue adjacent the respective source or sink based on a voltage and current delivered from the energy generator.

5. The system of claim 4 , wherein the impedance at the sources is calculated in a first manner, and the impedance at the sinks is calculated in a second manner different than the first manner.

6. The system of claim 4 , wherein the computer executable method is adapted to calculate the sink impedances as a percentage of the calculated source impedances.

7. A method of controlling an ablation procedure, comprising:

displaying on a user interface display a power interface and a plurality of graphical elements, each graphical element of the plurality of graphical elements representing a corresponding electrode carried by an ablation catheter in communication with an ablation energy generator;

in response to user interaction with the user interface display in a manner specific to one of the plurality of graphical elements, toggling the respective plurality of graphical elements between at least three visual indicators respectively representing an active source state having an active source visual indicator, an active sink state having an active sink visual indicator, and an inactive state with an inactive state visual indicator, wherein each of the three visual indicators are unique;

designating, via the user interface display, one or more of the electrodes with an active source state as one of a plurality of active source electrodes;

designating, via the user interface display, one or more of the electrodes with an active sink state as one of a plurality of active sink electrodes;

designating the plurality of active source electrodes together as a first pole in a bipolar mode, and designating the plurality of active sink electrodes together as a second pole in the bipolar mode; and

in response to one or more of the designations, connecting the plurality of active sink electrodes to a ground and connecting the plurality of active source electrodes to a source;

wherein each active source electrode of the plurality of active source electrodes is adapted to be individually adjusted at a distinct power level using the power interface displayed on the display,

wherein an energy density at each of the plurality of active sink electrodes is different from an energy density at each of the plurality of active source electrodes,

wherein an energy density at each of the plurality of active sink electrodes is no more than 20% less than an energy density at each of the plurality of active source electrodes.

8. The method of claim 7 , further comprising delivering ablation energy from the energy generator to the first pole.

9. The method of claim 7 , further comprising stopping energy delivery to any electrode if a monitored change in impedance indicates an abrupt and significant change in calculated impedance.

10. The method of claim 7 , further comprising stopping energy delivery to any electrode if a monitored impedance reaches a minimum threshold impedance or a maximum impedance threshold, which can occur automatically or via user input.

11. A system for monitoring an ablation procedure, comprising:

an ablation catheter including a plurality of ablation electrodes individually designable as being sources, sinks, or inactive;

an energy generator in communication with the ablation electrodes; and

a memory with a computer executable method stored thereon, the computer executable method adapted to calculate impedance associated with each of the sources and each of the sinks and tissue adjacent the respective source or sink based on a voltage and current delivered from the energy generator; and

a user interface comprising a display, the display including a plurality of impedance history regions, each one of the plurality of impedance history regions designated for one of the plurality of ablation electrodes;

wherein the system is adapted to display on each of the plurality of impedance history regions a line graph indicative of the respective calculated impedances over time for each of the selected plurality of ablation electrodes;

wherein each source electrode of the plurality of ablation electrodes is adapted to be individually adjusted at a distinct power level using a power interface displayed on the display;

wherein an energy density at each of a plurality of active sink electrodes is different from an energy density at each of a plurality of active source electrodes;

wherein an energy density at each of the plurality of active sink electrodes is no more than 20% less than an energy density at each of the plurality of active source electrodes.

12. The system of claim 11 , wherein the computer executable method is adapted to calculate the sink impedances as a percentage of the calculated source impedances.

13. The system of claim 11 , wherein the system is adapted to visually indicate on each of the plurality of impedance history regions if the respective impedance drops below a threshold impedance.

14. The system of claim 11 , wherein the system is further adapted to cease energy delivery to any of the plurality of ablation electrodes if the impedance for any of the plurality of electrodes increases or decreases abruptly.

15. The system of claim 14 , wherein the impedance at the sources is calculated in a first manner, and the impedance at the sinks is calculated in a second manner different than the first manner.