Reconstruction of 12-Lead Electrogram From Intracardiac Signals From Defibrillators During or After Implantation

Patients consenting to participate in the study may also undergo a baseline CT scan of the cest without contrast to allow for the geometrical characterization of their intracardiac electrodes from the ICD system in relation to the position of the 12-lead surface ECG electrodes which would be applied to the chest prior to the CT scan. This scan involves a small amount of radiation, a dose of approximately 1 rem. For comparison, radiation workers are permitted, by federal regulation, a maximum annual radiation exposure of 20 rems to the most sensitive organs of their body.