Extruding tube with increasing pitch helical conductor reinforcement for flexible tip

Abstract From the Canadian patent

Abstract, A body implantable intravascular lead with a first layer of plastic defining a tube having a precision lumen therein and at least one electrical conductor wrapped helically along the length of one or more plastic layers. The conductors are substantially parallel along the axis at each end for ease of connection to electrodes and the helical wrap of the conductors may vary throughout the length to form a first length having a first flexibility and a second length having a greater flexibility incapable of sustaining the same axial mechanical loading. The conductive wires are overlaid with one or more layers of plastic separately insulating the wires from each other.