Extraction of Electrocardiographic Interference from Multichannel Surface Electroenterogram

Surface electroenterogram (EEnG) is a novel technique for monitoring intestinal motility non-invasively. Nevertheless, surface EEnG recordings are contaminated by cardiac activity, respiratory artifact, movement artifact and other interferences. The goal of this work is to cancel the interference of electrocardiogram (ECG) on multichannel surface EEnG by means of a combined method of empirical mode decomposition (EMD) and independent component analysis (ICA). Surface signals from 4 different channels are decomposed using EMD. Resulting intrinsic mode functions are analyzed subsequently using ICA algorithm which permits to separate the ECG activity from the other activities. Signal components associated to ECG activity are removed and the processed signals are reconstructed by means of an inverse procedure. The results show that the proposed method allows extracting and canceling cardiac activity from surface EEnG. Therefore, this tool could be useful to enhance the quality of external EEnG recording and of similar biosignals.