Novel 3D-Printed Electrodes for Wearable Equine ECG Monitoring Systems

Equine electrocardiography (ECG) is an essential tool in veterinary cardiology, particularly in sports medicine. However, specific anatomo-physiological features (e.g., thick skin, hair coat, low cardiac mass-to-thoracic volume ratio) make the use of conventional electrodes inappropriate, measuring low-amplitude ECG signals, characterized by reduced signal-tonoise ratio (SNR). This study aimed to validate a novel customized 3D-printed electrode for equine ECG acquisition. The proposed electrodes are made of conductive carbon black- filled thermoplastic polyurethane (CB-TPU). Associated with a custom Arduino-based device, standard crocodile clips, and the novel 3D-printed electrodes were used to acquire 5-minute ECG recordings from a male 11-years-old horse in resting condition. The experiments were repeated two times. Quality and ECG features were computed to assess the goodness of the tracings. Results showed a SNR for the novel 3D-printed electrodes (15.00 dB) and standard crocodile probes (20.75 dB) higher than 10 dB, which is considered adequate for ECG analysis and interpretation. Despite there are differences in ECG noise-sensitive features (such as P-wave and T-wave features), overall ECG values remained close to clinical reference ranges, demonstrating that the novel proposed system is a promising solution for wearable equine ECG monitoring.