Motion Artifact Reduction in Ambulatory Electrocardiography Using Inertial Measurement Units and Kalman Filtering

Electrocardiography (ECG) using lightweight and inexpensive ambulatory ECG devices makes it possible to monitor patients during their daily activities and can give important insight in arrhythmias and other cardiac diseases. However, everyday activities cause several kinds of motion artifacts which deteriorate the ECG quality and thus complicate both automated and manual ECG analysis. In this paper, we discuss some of the challenges associated with long-term ambulatory ECG and propose a baseline wander compensation algorithm based on inertial measurement units (IMUs) attached to each ECG electrode. The IMUs are used for estimating the local electrode motion which in turn is used as the reference signal for baseline wander reduction. We evaluate the proposed algorithm on data gathered in clinical trials and show that the baseline wander is successfully removed, without compromising the ECG's morphology.