abstract |
A cardioversion/defibrillation device includes a lead catheter housing, two electrically independent conductors, and a pair of resilient helically coiled electrodes, one electrode coupled to each of the conductors. The distal ends of the electrodes are contained within an insulative, resilient coupling sleeve, such that the electrodes and sleeve form a loop when in the relaxed state, with the electrodes electrically isolated from one another. To facilitate body insertion and delivery to the electrode placement site, the electrodes and coupling sleeve are loaded into a delivery cannula, which elastically deforms the electrodes and sleeve into an elongate, narrow delivery configuration. Upon release from the delivery device, these components resiliently return to the loop configuration. If desired, an inextensible filament secured to the coupling sleeve is pulled proximally after deployment to selectively reconfigure the electrodes into two loops. Another modification involves several linear electrode branch segments, coupled to each electrode and projected inwardly of the loop or loops formed by the electrodes. |