Radiologic appearance of implantable cardiac defibrillators

Since the original descriptions of the radiologic appearance of implantable cardiac defibrillators by Lurie et al. [1] and Goodman et al. [2] in 1985, rapid growth has occurred in the complexity and variety of models available. Originally, all devices were surgically placed in or on the pericardium. Now, some devices are inserted by intravascular catheters with part of the device buried in the chest wall, avoiding the need for thoracotomy. Initially, these devices were used as defibrillators for treatment of tachyarrythmia and ventricular fibrillation. Now they serve as pacemakers for both tachy- and bradyarrhythmias and can act as cardioverters or defibrillators if required. Radiologists must be familiar with the appearances of these devices as their use becomes more widespread. In this article, the electrophysiology of these devices is briefly reviewed and the typical radiologic appearances are presented along with common radiologically recognizable complications.