Patent ID: 7818048

Claim:
A catheter comprising: an elongated catheter body having a proximal end, a distal end and at least one lumen extending longitudinally therethrough; a mapping assembly mounted at the distal end of the catheter body and comprising at least two spines, each spine having a proximal end fixedly attached at the distal end of the catheter body and a free distal end and carrying at least one electrode, wherein the mapping assembly is moveable between an expanded arrangement, in which each spine extends radially outward from the catheter body and bends back on itself at a mid-section such that the free distal end points generally back toward the catheter body to form a generally U-shape, and a collapsed arrangement in which each spine is disposed generally along a longitudinal axis of the catheter body; an irrigation tube extending through the catheter body and having an open distal end that is in communication with the outside of the distal end of the catheter body and a spine mounting assembly comprising: an outer mounting ring within an outer wall of the catheter body, and a mounting structure within the outer mounting ring, wherein the proximal ends of the spines are mounted in a channel between the outer mounting ring and the mounting structure, and wherein the at least one electrode of each spine comprises an electrode lead wire that extends through the channel between the outer mounting ring and the mounting structure a first non-conducting tube between the outer mounting ring and the spines; and a second non-conducting tube between the spines and the mounting structure.