An efficient algorithm for detecting the presence of a fetal QRS complex is presented. The proposed fetal QRS detection method computes the averaged magnitude of the difference between the fetal ECG signal and the reference signal to detect the fetal QRS event. The detected signal fetal QRS complexes are exponentially averaged to generate the template signal which can track the slowly varying shape of the fetal ECG signal. As an effort to obtain improved detection performances, two approaches of normalizing the fetal ECG signal and the template are considered.<<ETX>>

On Detecting the Presence of Fetal R-Wave Using the Moving Averaged Magnitude Difference Algorithm

A fetal ECG contains important indications about the health conditions of fetus, and could become a diagnostic tool of particular importance. One way to obtain the fetal ECG is by recording it on the mother’s abdomen. The recording is complicated by the existence of a strong maternal ECG and random contamination due to non cardiac sources. This research gives a study of separating the fetal ECG from the strong maternal trace and to separate the fetal ECG from the noise.

Blind separation of fetal ECG from single mixture using SVD and ICA

During pregnancy, the fetal physiological condition is carefully checked and monitored during the foetusÕ development. It is well known that the health of the foetus relies heavily on the nutrient and oxygen supply. The oxygen and nutrient supply is exchanged from the maternal vessel to the fetal vascular system via maternal placenta. The hypothesis that this research is trying to prove is that there may exist a strong synchronised relationship between the maternal and fetal cardiac systems, and the relationship may also correlate to the gestation period. The focus of the research was to extract fECG and mECG using non-invasive abdominal recordings and analyse the relationship between the parameters derived from the ECG signals. The research used derived parameters from the abdominal recordings to analyse the relationship between the maternal and fetal cardiac systems. To do this the fECG and mECG signals need to be separated from multiple abdominal and thoracic signals from open online source recordings. The principle of the ECG separation was based on independent component analysis (ICA) that considers multiple component signals statistically independent to each other. The pairs of extracted fECG and mECG signals are analysed on the time scale to investigate the synchronisation relationship. Being able to extract the heart rate of fetus and the mother independently is the key to determining the existence of a synchronised relationship between the separate cardiac systems. The findings from the fECG and mECG recordings at di erent gestational periods is that there is a direct relationship between the motherÕs cardiovascular system on the foetus, it may be caused by the nutritional influence during certain gestation periods.

Qianqian Wang

Papers

The synchronisation relationship between fetal and maternal cardiovascular systems