Wearable Magnetic Sensing Technologies for Cardiac and Respiratory Monitoring: A Review

Continuous monitoring of physiological parameters has become a cornerstone of modern healthcare, enabling early detection of pathological changes, timely interventions, and personalized treatment strategies. Among the most relevant physiological signals, cardiac and respiratory activity play a central role, as they directly reflect the status of the cardiovascular and pulmonary systems and are highly sensitive to both acute events and chronic conditions. Recent advances in wearable technologies have introduced compact, non-invasive devices for real-life monitoring. Alongside conventional approaches such as electrocardiography, plethysmography, or optical sensing, magnetic sensing technologies are increasingly being investigated as a promising alternative. Benefiting from progress in materials science, miniaturization, and flexible electronics, magnetic sensors offer high sensitivity, compatibility with soft and conformable substrates, and the possibility of unobtrusive, long-term monitoring. Their operating principles, including magnetoelastic, magnetoresistive, Hall effect, and magnetoimpedance mechanisms, enable versatile transduction of physiological phenomena causing changes in mechanical parameters into measurable signals. Applications demonstrated to date include cardiac monitoring through chest wall motion and pulse wave detection, as well as respiratory monitoring via chest wall movements and breathing airflow. Although research in magnetic sensors for cardiorespiratory monitoring is still at an early stage, with most studies focusing on proof-of-concept prototypes and feasibility tests under controlled conditions, these approaches already demonstrate considerable potential. This review highlights recent advances, explores emerging opportunities, and outlines future directions for clinical translation, with particular emphasis on the integration of magnetic sensors into wearable systems for personalized healthcare.