A catheter (10) comprising: an elongated catheter body (12) having proximal and distal ends and at least one lumen therethrough； the catheter body defining a longitudinal axis； an electrode assembly (18, 118) at the distal end of the catheter body, the electrode assembly having the proximal and distal ends and comprising a plurality of spines (120, 20, the spines comprising a plurality of electrodes (28), each spine comprising an arcuate electrode support portion (20B) and a generally straight distal portion (20D), the arcuate portion extending at an angle of 30 degrees to 80 degrees from the generally straight distal portion； an expander (22, 122) which has proximal and distal ends (22P and 22D), the expander forming a longitudinal axis of the assembly, the spines attached at their proximal ends to the catheter body and at their ends distal to the expander； at least one pull wire (35, 37 ) which extends through the expander, the pull wire having a distal end anchored in the expander at a distal location of the distal end of the catheter body and proximal of the distal end of the assembly； and a control handle (16) proximal to the catheter body, the control handle having an actuator adapted to move the at least one pull wire, wherein the expander is adapted for longitudinal movement in relation to the catheter body and by deviation in relation to the longitudinal axis.Un catéter (10)que comprende: un cuerpo del catéter alargado (12) que tiene extremos proximal y distal y por lo menos un lumen a través del mismo； el cuerpo del catéter definiendo un eje longitudinal； un montaje de electrodos (18, 118) en el extremo distal del cuerpo del catéter, el montaje de electrodos teniendo los extremos proximal y distal y comprendiendo una pluralidad de espinas (120, 20, las espinas comprendiendo una pluralidad de electrodos (28), cada espina comprendiendo una porción se soporte de electrodo arqueada (20B) y una porción distal generalmente recta (20D), la porción arqueada extend
