Systems and methods deploy an electrode from a catheter assembly. The systems and methods provide a catheter handle having a trigger lever adapted to carry an actuator rod. The actuator rod is adapted to cause movement of the electrode between a retracted position and an extended position. A pinion is carried by the trigger lever for engagement with a rack carried by the actuator rod. Compression of the trigger lever moves the rack along the actuator rod between a first position corresponding to the electrodes being in the retracted position and a second position corresponding to either the primed electrode firing position or the electrodes being in an extended position.