Impedance controlled tissue ablation apparatus and method

A cell necrosis apparatus for use in ablating target tissue, comprising, in operative condition:

• an elongated delivery device including a lumen;
• an energy delivery device including a plurality of electrodes, each electrode having a tissue piercing distal portion and being positionable in the elongated delivery device in a compacted state and preformed to assume a curved shape when deployed, the plurality of electrodes exhibiting a changing direction of travel when advanced from the elongated delivery device to a selected tissue site and defining an ablation volume when in said deployed state, said energy delivery device being operably connected to a source of energy;
• at least two of the plurality of electrodes being adapted for fluid delivery therethrough to at least one infusion port, wherein said at least two electrodes adapted for fluid delivery are operably connected to a fluid delivery device
• an energy control unit operably connected to (i) the source of energy, for controlling energy delivery to said energy delivery device, and to (ii) the energy delivery device for use in detecting impedance;
• and
• a fluid control operatively connected the fluid delivery device by which the amount of fluid infused from the device into the target tissue can be controlled in response to said detected impedance, wherein said fluid control is operable to provide independent control of infusion through the separate infusion lumens.