Piezoelectric Nanogenerators for Self-Powered Implantable Cardiac Monitoring Devices

Implantable cardiac monitors require continuous power sources that are safe, compact, and long-lasting, with battery replacement entailing significant patient risk. We demonstrate a ZnO-based piezoelectric nanogenerator that harvests cardiac mechanical energy to power implantable monitoring devices continuously. The device generates 4.8 μW/cm² at 1.2 Hz (resting heart rate frequency), providing sufficient power for real-time ECG monitoring with BLE wireless transmission. Biocompatibility assessment following ISO 10993 standards confirms no cytotoxicity, genotoxicity, or local tissue response. In vivo validation in a porcine model over 90 days demonstrates stable output with <8% power degradation, establishing feasibility for clinical translation.