A pacing lead for a left cavity of the heart, implanted in the coronary system. One lead includes a telescopic microcable including multiple distinct bare areas that form a network of stimulation electrodes. The microcable includes a diameter providing for insertion of the microcable within smaller portions of the coronary vein system. The diameter may be selected from between 0.5 and 2 French. The microcable includes multiple strands twisted together. At least some strands incorporate either a core of radiopaque material wrapped by a sheath of mechanically durable material, or vice-versa. The bare areas that form the network of stimulation electrodes are provided on outward-facing portions of at least some of the strands.
