Controlled discharge defibrillation electrode

Abstract

A defibrillation electrode for implantation on or about the heart and for connection to a defibrillation system. The electrode comprises a plurality of electrically conductive elements spaced apart and electrically connected together, thus, increasing the number of discharging edges on the electrode. In a first embodiment, the electrode comprises a plurality of concentric conductive rings electrically connected together. In a second embodiment, electrode comprises a plurality of conductive planar elements electrically connected together in a generally puzzle-like configuration. In a third embodiment, the electrode comprises electrically conductive wires wrapped around the length of a cardiac catheter. In a fourth embodiment, electrically conductive wires are concentrically spiralled into a spiral patch configuration. In a fifth specific embodiment, a plurality of electrically isolated active sites are provided on the distal portion of an endocardial catheter. In all of the above embodiments, the electrical discharge of energy from the electrode to the heart surface favors the conductive edges of the electrically conductive and connected components of the electrodes. Therefore, by increasing the number of conductive edges, a more uniform distribution of energy is delivered to the heart. Furthermore, each of the electrode configurations may be constructed without an insulative backing to further increase the efficiency of discharge.