A novel leadless pacemaker powered by a piezoelectric energy harvester
V Reddy, N J Melhem, D Shav, P Friedman, P Neuzil, E Marijon, P DefayeAbstract
Introduction
Energy harvesters that convert biomechanical energy into electrical power could be used for implantable devices, providing a near-infinite energy solution. While various energy harvesters with piezoelectric or triboelectric elements have been designed and applied to the cardiac environment, none have been successfully integrated into leadless pacemakers due to their size constraints or insufficient energy generation.
Purpose
This study aimed to test the performance of a novel self-sustaining leadless pacemaker, which operates on a proprietary inertial piezoelectric energy harvester (PEH) capable of generating the energy required for VVI therapy from the beating of the heart.
Method
A novel autonomous Leadless Pacing System (ALPS), including a leadless implant, a customized delivery tool catheter, and a home monitor, was developed. The leadless implant was designed to operate on the energy generated by a specially designed PEH that could fit inside the implant. The harvester’s energy was used to charge a small rechargeable backup battery, which provided the energy for a VVI single-chamber therapy. The leadless device and its dedicated delivery tool were then tested in vivo in an ovine model, adhering to the principles of laboratory animal care and with local ethical approval.
Results
The heart contractility creates harmonic movement in the heart tissue, which is transmitted into the PEH, resulting in the PEH acceleration. The leadless PEH components transform these mechanical forces into electric energy. In pre-clinical testing on an AV block ovine model (n=7), the device was able to pace the animals for 3 months, at 100% pacing, with an average pacing capture threshold of 0.9 (+/-0.5)V, with a pulse width of 0.366 msec, an average impedance of 570 (+/- 115) Ohm, and daily communication with the home monitor device.
Conclusion
This work demonstrates that a novel leadless pacemaker that utilizes a piezoelectric element to harvest the heart's mechanical energy to generate electrical energy successfully sustains VVI therapy. This approach is able to produce enough energy to maintain device longevity and support additional functionality, such as daily wireless communication with a home monitor, overcoming major limitations of leadless cardiac devices.