Leadless Pacing of the Heart Using Induction Technology: A Feasibility Study

OBJECTIVES: To develop a leadless pacemaker system based on induction technology and to investigate its feasibility and safety in the pig model. BACKGROUND: Despite tremendous technical advances during the last decades, cardiac pacing is still associated with a considerable rate of complications that can be primarily attributed to the leads. METHODS: The device consists of a transmitter unit implanted subcutaneously just above the heart and an endocardial receiver unit implanted in the apex of the right ventricle. The transmitter unit generates an alternating magnetic field that is converted into a voltage pulse by the receiver unit. In order to test feasibility, the receiver unit was attached to an electrophysiology catheter for signal recording and placed in the apex of the right ventricle of a pig. Subsequently, the receiver unit was implanted without external connection in the right ventricle. RESULTS: An alternating magnetic field of about 0.5 mT was generated by the transmitter unit in a distance of 3 cm. Voltage pulses with a duration of 0.4 ms and voltage amplitude of 0.6-1.0 V were generated. Using these pulse characteristics, a reliable stimulation of the heart could be achieved. A secure fixation of the receiver unit in the apex of the right ventricle could be obtained for the duration of this short-term study by using screw fixation. CONCLUSIONS: This study shows that induction technology is feasible for cardiac pacing. Typical voltage pulses could be generated by which an effectively stimulation in vivo could be achieved.