<；P>；PROBLEM TO BE SOLVED: To provide a catheter allowing distal end deflection, effectively utilizing the internal lumen of the catheter and not causing rapid displacement even when rotated around an axial center in a bent state. <；P>；SOLUTION: In the catheter, an electrode catheter 2 comprises a catheter tube 4 provided with at least one lumen 14 extending along an axial direction, and a coil spring 20 housed inside the lumen 14, whose cross section has a flat shape. The distal end of an operation wire 30 is connected to the side of the distal end 20a of the coil spring 20 positioned on the short diameter side of the flat shape of the coil spring 20. <；P>；COPYRIGHT: (C)2009,JPO&INPIT
