Changes in Signal Morphology of Hand-held ECG Devices with Dry Electrodes

Hand-held ECG devices often comprise dry electrodes for establishing an electrical connection to the patient's body.Due to motion artifacts, static electrode charges and DC amplifier offsets, these devices usually incorporate signal conditioning, such as filter stages, which can affect the ECG signal morphology.In this work, we implemented a MATLAB Simscape-based model to simulate the electrodeskin interface of dry electrodes and the corresponding measurement pathway of a hand-held ECG measurement device to investigate the influence of skin impedance, geometric factors and electrical circuitry on the signal morphology of an Einthoven I-lead heart cycle prototype.We performed synchronized measurements with the commercially available ECG device MyDiagnostick and a Philips patient monitor MX800 for reference purposes to identify device-related signal distortions.Results indicate a significant change in signal morphology of the ECG, exhibiting an increasingly biphasic P-wave with reduced amplitude, a negative S-peak and an inverted T-wave.