Evaluation of the fetal QT interval using non-invasive fetal ECG technology

Abstract

Non-invasive fetal electrocardiography (NI-FECG) is a promising alternative continuous fetal monitoring method that has the potential to allow morphological analysis of the FECG. However, there are a number of challenges associated with the evaluation of morphological parameters from the NI-FECG, including low signal to noise ratio of the NI-FECG and methodological challenges for getting reference annotations and evaluating the accuracy of segmentation algorithms. This work aims to validate the measurement of the fetal QT interval in term laboring women using a NI-FECG electrocardiogram monitor. Fetal electrocardiogram data were recorded from 22 laboring women at term using the NI-FECG and an invasive fetal scalp electrode simultaneously. A total of 105 one-minute epochs were selected for analysis. Three pediatric electrophysiologists independently annotated individual waveforms and averaged waveforms from each epoch. The intervals measured on the averaged cycles taken from the NI-FECG and the fetal scalp electrode showed a close agreement; the root mean square error between all corresponding averaged NI-FECG and fetal scalp electrode beats was 13.6 ms, which is lower than the lowest adult root mean square error of 16.1 ms observed in related adult QT studies. These results provide evidence that NI-FECG technology enables accurate extraction of the fetal QT interval.

Noninvasive fetal electrocardiography for the detection of fetal arrhythmias

“…We addressed these limitations in our study. Finally studies from Chia et al, Clifford et al, and Behar et al looked into the extraction of clinical parameters from the NI‐FECG morphology. Although these were original studies, all the fetuses included had no reported cardiac condition thus limiting the conclusions on whether the estimation of these physiological parameters is accurate enough and useful to provide actionable medical information.…”

“…Noninvasive fetal electrocardiography (NI‐FECG) is a promising noninvasive fetal diagnosis and monitoring alternative, which presents a number of advantages: low cost, possibility of local analysis (no need of long distance referral for pregnant women), information on atrial and ventricular activity, motion estimation, and possibility of continuous long‐term remote monitoring. The results of recent studies have shown the ability of the NI‐FECG to provide an accurate estimate of the fetal heart rate . However, to date, the clinical usability of NI‐FECG has rarely been studied.…”

Monitoring fetal maturation—objectives, techniques and indices of autonomic function

“…Analogously to the FMCG, the NI-FECG allows a deeper characterization of the electrophysiological activity by means of morphological analysis of its signal’s waveform. Promising early works on extracting morphological information from NI-FECG recordings have been published by Clifford et al (2011), Andreotti et al (2016a) and Behar et al (2016b).…”

Non-Invasive Fetal Monitoring: A Maternal Surface ECG Electrode Placement-Based Novel Approach for Optimization of Adaptive Filter Control Parameters Using the LMS and RLS Algorithms

“…A number of authors have used a rich variety of methods based on different principles for this purpose, as was mentioned in the previous section. For those cases in which only abdominal electrodes have been used to acquire the $a\mathrm{ECG}$ signals, the $f\mathrm{ECG}$ signals were extracted directly by means of linear [32,33,34,35,36,37,38,39,40,53,65,66,67,68,69,70,71,72] or nonlinear (for example, [73,74]) decomposition techniques [75,76]. …”