A catheter sheath for a basket catheter that includes a plurality of electrical leads, each having a proximal end and a distal end and a lumen extending from the proximal end to the distal end. Each electrical lead includes a tubular member of non-conductive material, a plurality of electrical conductors extending from the proximal end to the distal end laid on the non-conductive tubular member, and an outer layer of non-conductive material applied over the electrical conductors to cover the conductors. The catheter sheath further includes one or more electrodes on a distal portion of each electrical lead in electrical communication with at least one of the plurality of electrical conductors through the outer layer. An elongate shape-forming member is received in the lumen of each of the plurality of electrical leads. The shape-forming member imparts an arched shape to the distal portion of each of the electrical leads so as to form a basket shape to a distal portion of the catheter sheath. The plurality of electrical leads are bundled together at their distal ends and proximal the distal arched portion of each electrical lead.
