A microlead has a distal active portion formed by a microcable including an electrically conductive core coated with an insulation layer, with a plurality of exposed areas forming the stimulation electrodes. The microcable has a three-dimensional preshape inscribed in a cylindrical envelope volume so as to match the target vessel wall. The microcable includes a plurality of exposed areas regularly distributed over the circumference of the cylindrical envelope volume considered in axial projection, the exposed zones extending only over an angular sector of the microcable considered in cross section, said angular sector facing the outside of the envelope volume of the preshape.