Computational Characterization of the Terahertz Channel Through Cardiac Tissue for Leadless Pacemaker Communication

Leadless cardiac pacemakers eliminate several complications associated with conventional transvenous pacing leads; however, establishing a wireless communication pathway between an intracardiac device and a cardiac-surface interface remains challenging. This work proposes a cardiac communication architecture in which a leadless pacemaker communicates with an epicardial cardiac patch using terahertz (THz) signals. To characterize this link, THz propagation is investigated over 0.1–2 THz and communication distances of 0.1–2 mm. The myocardium is represented using heart-muscle dielectric properties, while connective-tissue properties provide a first-order representation of the epicardial medium. Frequency-dependent dielectric properties are incorporated into an analytical channel model to quantify spreading loss, molecular absorption loss, total path loss, molecular absorption noise, and channel capacity. The analytical propagation behavior is further examined using a frequency-domain full-wave electromagnetic model implemented in COMSOL Multiphysics. The influence of transmission parameters, including Gaussian-pulse duration and derivative order, on channel capacity is also investigated. The results characterize the dependence of THz propagation and channel capacity on frequency, distance, tissue properties, and pulse characteristics, providing a physical-layer basis for developing intracardiac-to-epicardial wireless communication systems for future cardiac monitoring applications.