Extract Fetal ECG from Single-Lead Abdominal ECG by De-Shape Short Time Fourier Transform and Nonlocal Median

Abstract

The multiple fundamental frequency detection problem and the source separation problem from a single-channel signal containing multiple oscillatory components and a nonstationary noise are both challenging tasks. To extract the fetal electrocardiogram (ECG) from a single-lead maternal abdominal ECG, we need to solve both challenges. We propose a novel method to extract the fetal ECG from a single-lead maternal abdominal ECG, without any additional measurement. The algorithm is composed of three components. First, the maternal and fetal heart rates are estimated by the de-shape short time Fourier transform (STFT), which is a recently proposed nonlinear time-frequency analysis technique. The beat tracking technique is the second component which is applied to accurately obtain the maternal and fetal R peaks. The third component consists of establishing the maternal and fetal ECG waveforms by the nonlocal median. The algorithm is tested on two real databases with the annotation provided by experts (adfecgdb database and CinC2013 database) and a simulated database (fecgsym), and provides the state-of-the-art results. We conclude that with the proposed algorithm, the fetal ECG waveform and the fetal heart rate could be accurately obtained from the single-lead maternal abdominal ECG.

Recovery of the fetal electrocardiogram for morphological analysis from two trans-abdominal channels via optimal shrinkage

“…to compare cardiac activities based on the OS theory. The algorithm is supported by solid mathematical foundation, and gives a convincing fetal R peak detection result on the publicly 49 available databases compared with those reported in [48,53,54], and the fECG morphology , the black tracking is the linearly combined ta-mECG, the blue tracking is the estimated mECG; in (b), (d) and (f), the red tracking is the rough fECG (rfECG) and the black tracking is the estimated fECG (fECG) depending on the optimal shrinkage. In ARR 3, we can easily identify the trigeminy pattern, and the P-waves are visible allowing to characterize the premature atrial contraction (PACs).…”

“…In our setup, we cannot get the mtECG, so these AF-based algorithms cannot be directly applied. However, recall that we are able to accurately estimate the mECG in the ta-mECG [48,53]. Therefore, we could view the estimated mECG signal as the reference channel.…”

How Nonlinear-Type Time-Frequency Analysis Can Help in Sensing Instantaneous Heart Rate and Instantaneous Respiratory Rate from Photoplethysmography in a Reliable Way

“…Furthermore, we could even apply the proposed method to other signals. For example, in the fetal ECG signal analysis, decomposing the maternal ECG signal from the fetal ECG signal is a critical step (Su and Wu, 2017). …”

Commentary: Computerised interpretation of fetal heart rate during labour (INFANT): a randomised controlled trial

“…Animal and human studies show that the current mode of ECG acquisition is outdated, imprecise, and discards important predictive information (Durosier et al, 2014; Li et al, 2015). To address this challenge, we recently developed and validated an algorithm for low-cost, portable high quality maternal, and fetal ECG monitoring capable of working with one or two maternal abdominal ECG channels to extract the fetal ECG (Li and Wu, 2017; Wu et al, 2017). While we need at least two channels for the algorithm introduced in (Wu et al, 2017), it could be applied to handle the single channel maternal abdominal ECG signal as generalized in (Li and Wu, 2017).…”

“…To address this challenge, we recently developed and validated an algorithm for low-cost, portable high quality maternal, and fetal ECG monitoring capable of working with one or two maternal abdominal ECG channels to extract the fetal ECG (Li and Wu, 2017; Wu et al, 2017). While we need at least two channels for the algorithm introduced in (Wu et al, 2017), it could be applied to handle the single channel maternal abdominal ECG signal as generalized in (Li and Wu, 2017). An important challenge is refining the algorithm to perform well in the case of twin pregnancies.…”