Detection of Onset and Offset of QRS Complex Based a Modified Triangle Morphology

摘要

It was important to detect onset and offset of QRS complex from ECG signal in order to accurately and effectively obtain some clinic parameters about ECG signal. Based on a conventional triangle morphology method, this paper introduced a modified triangle morphology algorithm (MTM). In the algorithm, a triangle shape was firstly built from the ECG signal processed by local normalization, and then the vertex angle of the formed triangle shape was calculated for each sample point. At last, the sample points, whose angles satisfied with some preset conditions, were regarded as onset or offset of QRS complex. Seven 12-lead ECG records obtained from the public standard database MIT-BIH twadb were employed to evaluate the proposed method. The results showed that MTM method could accurately detect onset and offset of QRS complex even though ECG signal was contaminated by baseline wander (BW), and these onset and offset of QRS complex identified by the proposed method were more reasonable than those by other methods.