An experimental study on a piezoelectric vibration energy harvester for self-powered cardiac pacemakers

BACKGROUND: Over the past half-century, cardiac pacing technology has been reported. In this study, we designed, prepared, and tested the performance of a self-energized cardiac pacemaker driven by piezoelectric vibration energy collection technology, which converts the kinetic energy of the heart into electrical energy. A record in vivo output current of 54 nA was obtained in an adult rat by the implanted piezoelectric transducer. METHODS: First, the kinetic energy of the heart was collected by an implanted piezoelectric energy collector and supplied to the cardiac pacemaker. Then, the heart was pierced from the outside, and the cardiac tissue was stimulated by the pacing electrode, and self-powered pacing. RESULTS: The average voltage and average current of the piezoelectric vibration energy harvester in vitro were 3.5 mV and 60 nA, respectively. After implantation of the device into rats, the average voltage and current were measured immediately and reached 3.2 mV and 54 nA, respectively. The average voltage and average current reached 3.0 mV and 48 nA after 1 week, and 2.1 mV and 31 nA after 12 weeks. The electrical performance of the self-powered pacemaker in this study is based on piezoelectric energy collection technology. The implanted piezoelectric vibration energy collector drives the pacemaker to generate electrical pulses, which directly stimulates the myocardial tissue through the epicardium to achieve the pacing effect. CONCLUSIONS: These results evidence the feasibility of the in-situ epicardial pacing strategy. This research will promote the design and development of self-powered cardiac pacemakers.