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arXiv · 2507.21263

In-vivo 6D heart motion analysis for emerging self-powered cardiac implants

Abstract

Self-powered intracardiac implant devices show great promise for future clinical applications due to their extended operational lifespan and the potential to reduce the need for high-risk repeat surgeries. This study investigates the feasibility of harvesting energy from cardiac motion through in vivo testing of intracardiac devices. Comprehensive three-dimensional translational and rotational cardiac motions are captured in a porcine model using a miniaturized 9-degree-of-freedom motion sensor implanted at six strategic epicardial sites. Kinematic criteria are developed to evaluate the energy harvesting potential of each implant site based on the available kinetic energy, acceleration, and jerk factors. The recorded heart motion signals are analyzed and applied to a conceptual energy harvester proposed to identify the optimal implant site. The results reveal that the left ventricular apex emerges as a preferable site for energy harvesting, particularly at moderate heart rates. These findings offer valuable insights into optimizing self-powered intracardiac implants, reducing dependency on battery replacements, and enhancing long-term patient safety.

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Milad Hasani, John Huber, Benedict Kjaergaard, Tomas Zaremba, Alireza Rezania, Sam Riahi. 2025-07-28. In-vivo 6D heart motion analysis for emerging self-powered cardiac implants. https://doi.org/10.1007/s10439-026-04037-5

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