The present invention relates to a catheter handle for steering a catheter shaft having a proximal region and a distal region and at least one steering wire having a distal end region secured at or near the distal end region of the catheter shaft and a proximal end, the catheter handle comprising: a catheter handle housing having the proximal end of the catheter shaft attached thereto; a steering controller carried by the catheter handle housing and having the proximal end of the at least one steering wire connected thereto, the steering controller being movable from a first position to a second position, the steering controller capable of applying tension to the at least one steering wire when the steering controller moves from the first position to the second position; and a lock mechanism for retaining the steering controller in the second position to prevent movement thereof, the lock mechanism movable between an unlocked position and a locked position and associated with the steering controller such that movement of the lock mechanism to the locked position restricts movement of the steering controller.