Multi-directional steerable catheters with control handle

A multi-directional steerable catheter (10) comprises a catheter body (12), a tip section (14) attached to the distal end of the catheter body, and a control handle (16) mounted at its distal end to the proximal end of the catheter body. The control handle comprises a housing (64) having a piston chamber extending therethrough and a piston assembly (65) having proximal and distal portions slidably mounted in the piston chamber and longitudinally movable between proximal and distal positions. The proximal portion of the piston assembly comprises a distal section (86) comprising a plurality of notches (96) at its proximal end, a proximal section comprising a plurality of longitudinal grooves (88) about its entire circumference separated by dividing walls having angled distal ends, and a circumferential recess (85) between the proximal section and distal section. The piston assembly further comprises a ring (98) rotatably mounted on the piston assembly (65) comprising a plurality of projections (110) that extend radially inwardly into the circumferential recess and that are capable of being received by the longitudinal grooves. The number of projections is less than the number of longitudinal grooves. The ring further comprises a plurality of teeth (108) at its distal end capable of being received by the notches. First and second puller wire anchors (76) are slidably disposed within a corresponding longitudinal groove. First and second puller wires (50) extend from the control handle, through a lumen in the catheter body and into a lumen in the tip section. The proximal end of each puller wire is fixedly attached to a separate puller wire anchor in the control handle. The distal ends of the puller wires are anchored at different locations in the tip section to form first curve and second curves in response to proximal movement of the first and second puller wires, respectively, relative to the catheter body.