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Figure 1 A schematic representation of the defibrillation shocking pathways. The dual-coil transvenous lead is positioned so that the tip is in the right ventricular apex. (A) The triad configuration is shown in which the distal coil in the right ventricle serves as the anode (+) for defibrillation. The pectoral can is connected electrically to the proximal atrial coil and serves as the cathode (–). (B) The transatrial configuration is shown in which the can alone serves as the cathode with the proximal coil as the anode.