Durable small gauge wire electrical conductor suitable for delivery of high intensity energy pulses

An apparatus, comprising:

• an electrical pulsing device configured and arranged to generate cardiac-directed electrical signals, and
• a fiber optic lead configured and arranged with a bend radius that is sufficiently small to allow the fiber optic lead to extend through a coronary vein of a patient, the fiber optic lead including:
• a drawn fiber core that is an insulator comprising silica or glass,
• a coaxial conductive metal layer directly on the core and configured and arranged to carry the electrical signals generated by the electrical pulsing device toward a distal end of the conductor,
• an electrode at the distal end of the lead, the electrode electrically connected to the coaxial conductive metal layer,
• a biocompatible coating;
• and
• an anchoring system for stabilizing the lead against unwanted migration;
• wherein the fiber optic lead is sufficiently flexible to bend to a radius of about 8 to 10 times the fiber core diameter without damage.