An implantable, externally powered radiotelemetric system for long-term ECG and heart-rate monitoring.

An externally inductive powered implantable ECG radiotelemetry unit has been developed for continuous long-term measurements of cardiophysiological changes following administration of cardiotoxic drugs. The power density distribution (320 kHz) inside the cage has been measured to be 3-11 mW/cm2. The implantable unit has a volume of 38 X 22 X 8 mm and a mass of 9 g, and has been tolerated by the animal (guinea pig) during a continuous registration period of 6 months.