CATHETER WITH BIASED PLANAR DEFLECTION

An improved steerable catheter (10) with biased, in-plane bi-directional deflection has an elongated catheter body (129, a deflectable intermediate section (14) having a tubing with at least a first and a second off-axis opposing lumens (30, 31, 32, 33) for puller wires (42), and a control handle (16) at a proximal end of the catheter body. The deflectable intermediate section includes at least two elongated bias members (54) that extend along the length and lie on a plane perpendicular to the plane of deflection so as to resist flexure outside of the plane of deflection. The deflectable intermediate section has an integrated tubular construction that includes an inner layer (50), a braided mesh (52) surrounding the inner layer and an outer layer (56), where the bias members can be situated between the inner layer and the braided mesh, or between the braided mesh and the outer layer.