Compact long-term recorder for the transabdominal foetal and maternal electrocardiogram

Abstract

Foetal heart rate (FHR) monitoring is a proven means of assessing foetal health during the antenatal period. Currently, the only widely available instrumentation for producing these data is based on Doppler ultrasound, a technology that is unsuitable for long-term use. For nearly a century, it has been known that the foetal electrocardiogram (FECG) can be detected using electrodes placed on the maternal abdomen. Although these signals suggest an alternative means of FHR derivation, their use has been limited owing to problems of poor signal-to-noise ratio. However, the eminent suitability of the transabdominal FECG for long-term FHR monitoring has suggested that perseverance with the technique would be worthwhile. The paper describes the design, construction and use of a compact, long-term recorder of three channels of 24 h antenatal transabdominal data. Preliminary use of the recorder in around 400 short recording sessions demonstrates that FHR records of equivalent quality to those from Doppler ultrasound-based instruments can be extracted from such data. The success of FHR derivation is, on average, around 65% of the recording period from around 20 weeks gestation (although this figure is reduced from around 28-32 weeks, and the success rates exhibit a wide range when individual subjects are considered). These results demonstrate that the technique offers, not only a means of acquiring long-term FHR data that are problematic to obtain by other means, but also a more patient-friendly alternative to the Doppler ultrasound technique.

An Efficient Method for Fetal Electrocardiogram Extraction from the Abdominal Electrocardiogram Signal

“…Therefore, the maternal contribution was not totally suppressed at the point in the FECG signal. [9] Adaptive algorithm 85.00 Azad [7] Fuzzy approach 89.00 Pieri et al [10] Matched filter 65.00 Ibrahimy et al [11] Statistical analysis 89.00 This research Artificial intelligence 93.75 and correlation…”

Non Invasive Foetal Monitoring with a Combined ECG - PCG System

“…FECG (Echeverria et al, 1998;Pieri et al, 2001) has also been extensively studied, but it is difficult to obtain high quality recordings, mainly because of the very poor signal to noise ratio (SNR). Moreover, the automated analysis of FECG is less accurate than that of CTG (Varady et al, 2003).…”

“…In FHS extraction, S1 is often considered as a good time marker for the heart beat, because of its high energy with respect to the other portions of the FPCG signal, and its lower morphologic variability (Pieri et al, 2001;Ahlstrom et al, 2008). Thus, once each S1 is detected, the correspondent FHR series can be easily estimated measuring the time between each S1.…”

Non- Invasive Method of Fetal ECG Extraction Using Hilbert Transform

“…Various techniques have been employed to address this problem, including digital filtering and cross-correlation with template [2], template subtraction [3], matched filtering [4], linear combination of phase difference corrected signals [5], independent component analysis (ICA) [6,7] and time-frequency analysis [8][9][10][11][12]. In this paper, an integrated approach for fetal heart beat detection is proposed, combining the Hilbert transform (HT) and non-linear state-space projections (NSSPs).…”