An Approach for Self-Powered Cardiovascular Monitoring Based on Electromagnetic Induction

Though medical implantable devices are highly suitable for continuous and real-time patient monitoring, their battery replacement is a costly and complicated procedure. To extend the functional life of medical implants, energy harvesting methods have been investigated that convert the motions of the cardiovascular system to electrical energy. In this paper, we present the potential of such an energy harvester to operate as a sensor for cardiovascular parameters estimation, thus enabling the realization of a novel self-powered implantable cardiovascular monitor. This energy harvester is based on electromagnetic induction and exploits a conductive coil that moves along with an artery inside a magnetic field, applied by two permanent ring magnets. A similar device was fabricated and in order to test it, an experimental setup was developed that simulates arterial wall motion. Our in vitro experiments demonstrated that the voltage induced in the coil is linearly related with arterial wall velocity and heart rate (coefficient of determination R-2 > 0.99). Moreover, the induced voltage was associated with blood pressure and the deforming artery's radius through a second-order polynomial fit (R-2 > 0.99).