Radiographic pseudofracture of bipolar pacemaker wire

Radiology of cardiac devices and their complications

This article familiarizes the reader with several different cardiac devices including pacemakers and implantable cardioverter defibrillators, intra-aortic balloon pumps, ventricular assist devices, valve replacements and repairs, shunt-occluding devices and passive constraint devices. Many cardiac devices are routinely encountered in clinical practice. Other devices are in the early stages of development, but circumstances suggest that they too will become commonly found. The radiologist must be familiar with these devices and their complications.

Potential of gallium-based leads for cardiac rhythm management devices

We propose the use of gallium (Ga), a metal that is liquid at physiological temperatures, or one of its alloys, for use as the conducting material in the leads of implantable pacemakers or cardioverter defibrillators. It is proposed that a liquid conductor will make these leads more pliable and thus less susceptible to fracture in situ. As an initial step towards utilizing liquid gallium in leads, the biocompatibility of Ga was investigated via cytotoxicity, hemocompatibility, and intracutaneous injection testing. Unipolar pacing Ga prototypes were fabricated by adapting existing pacemaker leads. The electrical impedance and pulse transmission ability of these leads were examined. Ga was well tolerated both in vitro and in vivo. Additionally, the Ga prototypes conductors behaved as low magnitude resistances that did not distort pulses as generated by conventional pacemakers. These results indicate that Ga is an appropriate material for implantable cardiac stimulators and will be a focus of our liquid metal prototypes.