2013

Intrapartum Fetal and Maternal Heart Rate Ambiguity- a Comparison of Doppler Ultrasound CTG and  the Abdominal Fetal Electrocardiogram with Maternal Electrocardiogram

Reinhard J, Hayes-Gill BR, Schiermeier S, Hatzmann W, Heinrich TM, Louwen F.

Gynecologic and Obstetric Investigation

2013; 75: 101-8

OBJECTIVE / AIMS: To investigate the presence of signal ambiguity of intrapartum fetal heart rate (FHR) monitoring during delivery by comparing simultaneous CTG,  abdominal fetal electrocardiogram (ECG) with continuous maternal ECG.

METHODS: A total of 144 simultaneous CTG (Corometrics 250 series©), abdominal fetal ECG (Monica AN24^TM) and maternal ECG (Monica AN24^TM) recordings were evaluated.

MAIN OUTCOME MEASURES: When the FHR is within 5 bpm of the maternal heart rate (MHR) acquired from the ECG it is classified as “MHR/FHR ambiguity”. Statistical analyses were performed with the Fisher’s exact and the Wilcoxon signed rank tests.

RESULTS: Comparison of abdominal fetal ECG against CTG demonstrates significantly less “  MHR/FHR ambiguity” in both the first stage (mean 0.70% versus 1.22%, p<0.001) and 2nd stage of labour (mean 3.30% versus 6.20%, p<0.001).

CONCLUSION: Intrapartum FHR monitoring in daily practice via the CTG modality provides significantly more “MHR/FHR ambiguity” than abdominal fetal ECG, which also provides additional information on the MHR.

2013

Antenatal architecture and activity of the human heart

Pervolaraki. E,  Anderson. R, Benson. A, Hayes-Gill. B, Holden. A,  Moore. B.J.R,  Paley. M.N,  Zhang. H

Published online February 21, 2013 doi: 10.1098/​rsfs.2012.0065 Interface Focus 6 April 2013 vol. 3 no. 2 20120065

Abstract: We construct the components for a family of computational models of the electrophysiology of the human foetal heart from 60 days gestational age (DGA) to full term. This requires both cell excitation models that reconstruct the myocyte action potentials, and datasets of cardiac geometry and architecture. Fast low-angle shot and diffusion tensor magnetic resonance imaging (DT-MRI) of foetal hearts provides cardiac geometry with voxel resolution of approximately 100 µm. DT-MRI measures the relative diffusion of protons and provides a measure of the average intravoxel myocyte orientation, and the orientation of any higher order orthotropic organization of the tissue. Such orthotropic organization in the adult mammalian heart has been identified with myocardial sheets and cleavage planes between them. During gestation, the architecture of the human ventricular wall changes from being irregular and isotropic at 100 DGA to an anisotropic and orthotropic architecture by 140 DGA, when it has the smooth, approximately 120° transmural change in myocyte orientation that is characteristic of the adult mammalian ventricle. The DT obtained from DT-MRI provides the conductivity tensor that determines the spread of potential within computational models of cardiac tissue electrophysiology. The foetal electrocardiogram (fECG) can be recorded from approximately 60 DGA, and RR, PR and QT intervals between the P, R, Q and T waves of the fECG can be extracted by averaging from approximately 90 DGA. The RR intervals provide a measure of the pacemaker rate, the QT intervals an index of ventricular action potential duration, and its rate-dependence, and so these intervals constrain and inform models of cell electrophysiology. The parameters of models of adult human sinostrial node and ventricular cells that are based on adult cell electrophysiology and tissue molecular mapping have been modified to construct preliminary models of foetal cell electrophysiology, which reproduce these intervals from fECG recordings. The PR and QR intervals provide an index of conduction times, and hence propagation velocities (approx. 1–10 cm s−1, increasing during gestation) and so inform models of tissue electrophysiology. Although the developing foetal heart is small and the cells are weakly coupled, it can support potentially lethal re-entrant arrhythmia

2012

 Non-invasive Fetal ECG registration using Monica AN24 fetal monitoring system

Department of Obstetrics, Leiden University Medical Center

W.J. Kist, R. Franken,  S.Vink, N.Blom, L. Rozendaal, D.Oepkes

Poster presesentation at the

16th International Conference on Prenatal Diagnosis 

Miami, Florida, USA

3-6 June 2012

Background: Reliable non-invasive recording of the fetal electrocardiogram (fECG) has been pursued by obstetric researchers for decades. Many fetal pathologic conditions could be monitored more accurately if fECG could be obtained. The Monica AN 24, a new, portable fetal monitoring device can make 20 hour recordings of fetal and maternal cardiac electrical signals and uterine activity with 5 abdominal stickers.

Objective: Aim of our study was to evaluate the feasibility of obtaining interpretable fECG signals of human fetuses in the second and third trimester.

Material and methods: Prospective cohort study in uncomplicated singleton pregnancies.  Registrations of 30 minutes were made from 14 to 38 weeks’ gestation. Primary outcome was success rate of obtaining a fECG with recognizable P-wave, QRS complex and ST segment, analyzable with the DK 1.4a software. Secondary outcome was influence of BMI and gestational age.

Results: In total 178 registrations were made in 82 pregnancies. In 138 (78%), a fECG could be analyzed. From 14-22 weeks (n=57), success-rate was 86%.BMI did not influence success-rate.

Conclusion: With the Monica AN 24 andDK 1.4a software, we could record and analyze a fetal ECG in almost 80% of pregnancies in the second and third trimester.BMI played no role. This device has the potential to become an important additional tool in fetal diagnosis and monitoring of the many conditions that affect fetal cardiac function.

2012

Intrapartum signal quality with external fetal heart rate monitoring: a two way trial of external Doppler CTG ultrasound and the abdominal fetal electrocardiogram

Reinhard.R,  Hayes-Gill. BR,  Schiermeier.S, Hatzmann.W, Herrmann.E, Heinrich.T, Louwen.F

Maternal-Fetal Medicine

Arch Gynecol Obstet

Published online 20.06.2012

Abstract

The objective of this study was to assess the fetal heart rate (FHR) signal quality of non-invasive abdominal fetal electrocardiogram (fECG) in comparison to the Doppler ultrasound cardiotocogram (CTG) during the first and second stage of labour.

Study design: This was a prospective observational study of non-invasive fECG using five abdominally sited electrodes against the traditional Doppler ultrasound CTG probe on 144 patients. Data were analysed for signal quality before and after outlier removal.

Results: Abdominal fECG signal quality was significantly better during the first stage of labour in comparison to Doppler CTG (median fECG reliability of 95.7 % vs.median 87.3 % for Doppler, p.001), whereas during second stage of labour, equivalence was demonstrated(p[0.05). For the first and second stage of labour, fECG showed 106/135 (78.5 %) and 46/98 (46.9 %) women having fetal signal loss below 20 %, respectively. Similarly, Doppler ultrasound demonstrated 104/135 (77.0 %) and 51/98 (52.0 %) women having fetal signal loss below 20 % during first and second stage of labour, respectively.

Conclusion: The non-invasive abdominal fECG presents an improved FHR signal quality during the first stage of labour and an equivalent signal quality during the second stage.

2012

Fetal and maternal heart rate confusion during intra-partum monitoring: comparison of trans-abdominal fetal electrocardiogram and Doppler telemetry.

Stampalija T, Signaroldi M, Mastroianni C, Rosti E, Signorelli V, Casati D, Ferrazzi EM

The Journal of Maternal - Fetal & Neonatal medicine

2012 Aug;25(8):1517-20. Epub 2011 Dec 3.

Objective: To compare intra-partum performance of trans-abdominal electrocardiogram with Doppler telemetry.

Methods: In this prospective longitudinal study, simultaneous monitoring with trans-abdominal ECG and Doppler telemetry was performed in 41 uncomplicated term singleton pregnancies during labour. Results: The overall success rate for FHR monitoring was similar between trans-abdominal ECG and Doppler telemetry (88.5 ± 16.7% vs 89.4 ± 7.6%), except for the second stage of labour. A significantly higher rate of confusion (p < 0.001) between fetal and maternal heart was found for Doppler telemetry (4.5 ± 4.5%) compared with trans-abdominal ECG (1.3 ± 1.9%), especially in the second stage and during maternal movements.

Conclusions: Trans-abdominal ECG monitoring is feasible, with comparable success rate to traditional Doppler telemetry, without interfering with maternal mobility or requiring midwife intervention. The reduction in maternalfetal heart rate confusion from trans-abdominal ECG could reduce incorrect obstetric interpretation.

2012

Prenatal Foetal Non-invasive ECG instead of Doppler CTG – A Better Alternative?
N. Sänger, B. R. Hayes-Gill, S. Schiermeier,W. Hatzmann, J. Yuan, E. Herrmann, F. Louwen, J. Reinhard
Geburtsh Frauenheilk 2012; 72: 630–633
 

Introduction: This study aimed to evaluate foetal signal quality obtained using an antenatal foetal ECG system (Monica 24™) and compare it with Doppler ultrasound CTG monitoring (Corometrics ® 250 series).
Material and Methods: Seventy pregnant women (gestational age: between 20 + 0 weeks and 40 + 0 weeks) were examined using the Monica AN24™ system and also underwent Doppler CTG. The signal quality of both methods was compared and correlated with gestational age and pre-pregnancy body mass index (BMI).
Results: Overall, ECG had a signal quality of 77.4% and CTG had a signal quality of 73.1% (p > 0.05). In gestational weeks (GW) 20–26, the signal quality of ECG was significantly better compared to that obtained with CTG (75.5 vs. 45.3%; p = 0.003),
while in GW 27–36, the signal quality was better with CTG (72.3 vs. 83.0%, p = 0.001). No difference in signal quality was found between the two methods after the 37th GW (87.7 vs. 86.1%; p > 0.05). CTG showed a statistically significant correlation with BMI (rho 0.25, p < 0.05) while ECG showed no such correlation.
Conclusion: The use of non-invasive ECG is particularly indicated in the early weeks of pregnancy, while CTG offers superior results during the vernix period. There was no difference in signal quality after the vernix period. The signal quality with ECG was found to be independent of BMI, while the signal quality of CTG deteriorated with increasing
BMI.
 

2012

Accuracy and reliability of fetal heart rate monitoring using maternal abdominal surface electrodes

Cohen W, Ommani S, Hassan S, Mirza F, Solomon M, Brown R, Schifin B, Himsworth J, Hayes-Gill B

  August 2012

Acta Obstetricia et Gynecologica Scandinavica

2012 Nordic Federation of Societies of Obstetrics and Gynecology

Abstract

Objective. Compare the accuracy and reliability of fetal heart rate identification from maternal abdominal fetal electrocardiogram signals (ECG) and Doppler ultrasound with a fetal scalp electrode.  Design. Prospective open method equivalence study. Setting. Three urban teaching hospitals in the Northeast United States. Sample. 75 women with normal pregnancies in labor at >37 weeks of gestation. Methods. Three fetal heart rate detection methods were used simultaneously in 75 parturients. The fetal scalp electrode was the standard against which abdominal fetal ECG and ultrasound were judged. Main outcome measures. The positive percent agreement with the fetal scalp electrode indicated reliability. Bland–Altman analysis determined accuracy. The confusion rate indicated how frequently the devices tracked the maternal heart rate.  Results. Positive percent agreement was 81.7 and 73% for the abdominal fetal ECG and ultrasound, respectively (p = 0.002). The abdominal fetal ECG had a lower root mean square error than ultrasound (5.2 vs. 10.6 bpm, p < 0.001). The confusion rate for ultrasound was 20-fold higher than for abdominal ECG (8.9 vs. 0.4%, respectively, p < 0.001). Conclusion. Compared with the fetal scalp electrode, fetal heart rate detection using abdominal fetal ECG was more reliable and accurate than ultrasound, and abdominal fetal ECG was less likely than ultrasound to display the maternal heart rate in place of the fetal heart rate.
 

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2012

Average acceleration and deceleration capacity of the fetal heart rate in normal pregnancy and in pregnancies complicated by fetal growth restriction

E. M. Graatsma, E.J.H. Mulder, B. Vasak, S.M. Lobmaier, S. Pildner von Steinburg, K.T.M Schneider, G. Schmidt, G.H.A. Visser

The Journal of Maternal –Fetal and Neonatal Medicine, 2012;25(12):2517-2522

Objective: To study fetal heart rate (FHR), its short term variability (STV), average acceleration capacity (AAC), and average deceleration capacity (ADC) throughout uncomplicated gestation, and to perform a preliminary comparison of these FHR parameters between small-for-dates (SFD) and control fetuses.  Method: Prospective observational study of 7 h FHR-recordings obtained with a fetal-ECG monitor in the second half of uncomplicated pregnancies (n=90) and pregnancies complicated by fetal SFD (n=30).  FHR and STV were calculated according to established analysis. True beat-to-beat FHR, recorded at 1 ms accuracy, was used to calculate AAC and ADC using Phase Rectified Signal Averaging (PRSA). Mean values of FHR, STV, AAC, and ADC derived from recordings in SFD fetuses were compared with the reference curves. Results: Compared with the control group the mean z-scores for STV, AAC, and ADC in SFD fetuses were lower by 1.0 SD, 1.5 SD, and 1.7 SD, respectively (p<0.0001 for all comparisons). In SFD fetuses, both the AAC and ADC z-scores were lower than the STV z-scores (p<0.02 and p<0.002, respectively). Conclusion: Analysis of the AAC and ADC as recorded with a high resolution fECG recorder may differentiate better between normal and SFD fetuses than STV.

2012

Accuracy and Reliability of Uterine Contraction Identification Using Abdominal Surface Electrodes

Barrie Hayes-Gill, Sarmina Hassan, Fadi G. Mirza, Sophia Ommani, John Himsworth, Molham Solomon, Raymond Brown, Barry S. Schifrin and Wayne R. Cohen

Clinical Medicine Insights: Women’s Health 2012:5 65–75

Abstract
Objective: To compare the accuracy and reliability of uterine contraction identification from maternal abdominal electrohysterogram and tocodynamometer with an intrauterine pressure transducer.
Methods: Seventy-four term parturients had uterine contractions monitored simultaneously with electrohysterography, tocodynamometry, and intrauterine pressure measurement.
Results: Electrohysterography was more reliable than tocodynamometry when compared to the intrauterine method (97.1 versus 60.9 positive percent agreement; P , 0.001). The root mean square error was lower for electrohysterography than tocodynamometry in the first stage (0.88 versus 1.22 contractions/10 minutes; P , 0.001), and equivalent to tocodynamometry in the second. The positive predictive values for tocodynamometry and electrohysterography (84.1% versus 78.7%) were not significantly different, nor were the false positive rates (21.3% versus 15.9%; P = 0.052). The sensitivity of electrohysterography was superior to that of tocodynamometry (86.0 versus 73.6%; P , 0.001).
Conclusion: The electrohysterographic technique was more reliable and similar in accuracy to tocodynamometry in detecting intrapartum uterine contractions.

2012

Is the fetal heart rate affected by uterine contractions during pregnancy? A pilot study

Sletten. J, Kiserud. T, Kessler. J

Acta Obstet Gyn Scan, 2012. 91(Supplement s159): p. 59-149

Poster presented at the Nordic meeting of Obstetrics and Gynecology in June 2012

Background;  New monitoring technology enables long-term recording of the fetal heart rate without discomfort for the mother. The initial aim of this pilot study was to test the feasibility and success rate of a new fetal Holter monitor. We observed linear correlations between maternal and fetal heart rates, and hypothesised that uterine activity during pregnancy affects the fetal heart rate.

Method: Twelve pregnant women were monitored with a potable Holter device, which (Monica AN24, Monica Healthcare Ltd), which recorded the maternal and fetal electrocardiogram (ECG) and electrohystergram (EHG) by five abdominal electrodes. The recordings were performed outside the hospital and participants were not imposed any restrictions for their activities during the time of the recording.  Data on the fetal and maternal heart rates and the strength of uterine contractions was available in 2 seconds epoch during the entire recording. The EHG data were categorised into a basal level, and slightly, moderately or severely increased uterine activity (UA). Each participant’s data was analysed separately.

Results: The recordings lasted 18.8 hours (range 17.4-19.3) and were taken at a gestational age of 32+6 weeks (range 25+0-38+2). Data on maternal and fetal ECG was available for 99.9% and 73.1% of the recorded time, respectively. There was a linear correlation between maternal and fetal heart rates in 11/12 cases. Beta coefficient was at mean 0.189; for participants < 36 weeks (N=7) 0.106 and for those ≥ 36 weeks (N=5) 0.305. In all participants UA affected the fetal heart rate. Compared to the basal tone, mild, moderate and severe UA were associated with a mean increase of the fetal heart rate by 1.37, 4.1 and 5.9 beats/min respectively

Conclusion: The relationship between fetal and maternal heart rates could reflect a circadian rhythmicity in the mother and the fetus. Uterine contractions during pregnancy, accompanied by increased umbilical blood flow, may represent a physiological challenge for the development and adaptation of the fetal cardiovascular system.   

2011

Aim: To evaluate the feasibility of trans-abdominal ECG (aECG) monitoring with portable device (Monica AN24) during outpatient labor induction.

Methods: Low risk post term women induced with slow release dinoprostone pessaries (10mg) were allowed home for up to 24 hours, whilst aECG, uterine activity and maternal heart rate were continuously monitored. aECG signal was transmitted from a portable device to a hospital PC via ordinary mobile phone (Bluetooth) using Trium CTG Online. aECG traces were displayed in real time on a hospital PC and intermittently reviewed by hospital staff. Women were asked to complete diaries and a subgroup was invited for face to face interview.

Results: 70 recruited women went home during the induction. 17 (24%) woman stayed at home for >5 hours, 19 (27%) between 5-10, and 34 (49%) women for >10 hours. 52 (74%) women returned with ruptured membranes, spontaneous labor, fallen pessary. 8 (11%) were recalled for signal loss, 3 (4%) with non- reassuring trace and 7 (10%) electively after 24 hours. 55 (79%) women had a vaginal delivery.
51 diaries were returned. Participants preference showed that, during labour induction, women would rather be at home (92%) than in hospital (94%); they were very comfortable wearing the device (90%) and were very satisfied with outpatient monitoring (90%).

Conclusion: Continuous aECG monitoring of ambulatory women undergoing induction of labor at home is feasible and acceptable to women. The quality of remote signal was of sufficient quality to allow clinical decision making in real time.

2011

Obective: To evaluate fetal heart rate, obtained by trans-abdominal ECG R-R intervals, by power spectral density (PSD), and compare normal values with findings obtained in acidemic fetuses.
Methods: Trans-abdominal fetal ECG with Monica AN24 device was performed in labour in uncomplicated term pregnancies. Thirty-six ECG traces were collected at the beginning of labour from patients that delivered neonates with normal outcome (Ph>7.20, BE <5, Apgar at 1 and 5 minutes 10-10). Comparative analysis was performed with two cases with adverse outcome (pH< 7.0, BE> 12, Apgar at 5 minute ≤ 7). Thirty minutes records were used for each patient. Due to non-uniformity sampled data a Lomb-Scargle peridogram was used to estimate the power spectral density at ultra-low (0.00083-0.003 Hz), very-low (0.003-0.04 Hz), low (0.04-0.15 Hz), high (0.15-0.4 Hz) and very-high frequencies (0.4-0.92 Hz).
Results; The graph shows the data represented through box plots. The boxes represent the inter-quartile range and the whiskers represent the most extreme data points, which are not considered outliner. The two fetuses with an abnormal hypoxic outcome did not show any difference in power analysis values since their findings fitted within the interquartile range of normal cases.
Conclusion: This is the first reported analysis in non-uniformly sampled data by means of Lomb-Scargle periodgram.
We were able to define the relative power spectral analysis of ultra-low, very-low, low, high and very-high frequencies of trans-abdominal fetal ECG in early labour in healthy fetuses. Two fetuses that subsequently developed acidemia did not show any difference in power spectral densities in early stage of labour. This findings suggests that possible change of the autonomous nervous system balance may not present early in labour in cases where intra-partum asphyxia confirmed at birth develops progressively during the labour.

2011

Fetal and maternal heart rate confusion during intra-partum monitoring: comparison of trans-abdominal fetal ECG and Doppler telemetry

Stampalija. T, SignaroldI. M, Mastroianni. C, Rosti. E, Loi.G, Ferrazzi. E

Paper presented at the
Meeting of Society for Maternal-Fetal Medicine (SMFM) California USA

The 31st Annual Meeting February 2011

Objective: Fetal monitoring by Doppler is well established standard of care. Doppler signal quality, signal loss and FHR/MHR confusion are the main pitfalls. Restriction of mobility during the first stage of labour by Doppler probes is the second major problem, since mobility reduces the length of labour (Cochrane Systematic Review, 2009). The availability of non invasive FHR monitoring technique that would possibly reduce signal errors, without interfering with patient mobility, might carry significant advantages. New leadless, non invasive trans-abdominal fetal and maternal ECG monitoring is available.

Objective: to compare the FHR performance and FHR /MHR confusion of non invasive trans-abdominal fetal ECG (tafECG)) with standard Doppler telemetry during labour.

Study design: Patients with uneventful term pregnancies were simultaneously monitored during labour with ta-fECG (Monica AN24) and leadless Doppler system (Phililps Avalon CTS). The FHR and MHR ¼ sec data values from both systems were logged digitally. The overall success rate (SR) and FHR/MHR confusion rate (CR) were evaluated. While none of the above systems represent the gold standard, FHR/MHR confusion was considered to have occurred when the FHR value was within 5 beats of the MHR value.
Results: 41 patients were recruited. Two cases were excluded when no fetal ECG signal was obtained by Monica AN24 due to high electrical noise. The analysis was performed on 39 patients. Overall (1st and 2nd stage) SR in labour for ta-fECG was 83% and 89% for Doppler leadless system.
Conclusion: ta-fECG monitoring in labour

Is feasible and represents more comfortable solution for the patient. Although, in our cohort, the overall SR from leadless Doppler system is better, the confusion of FHR/MHR is significantly higher in comparison with Ta-fECG, especially in II stage. By displaying simultaneously FHR and MHR traces, trans-abdominal ECG system allows instant recognition of possible FHR/MHR confusion that could otherwise cause hesitation or inappropriate obstetrical intervention.

2011

Uterine Activity Monitoring during Labour – A Multi-Centre, Blinded Two-Way Trial of External Tocodynamometry against Electrohysterography

J. Reinhard , B. R. Hayes-Gill , S. Schiermeier , H. Löser , L. M. Niedballa , E. Haarmann , A. Sonnwald ,
W. Hatzmann , T. M. Heinrich , F. Louwen

10.1055/s-0031-1291210 Z Geburtsh Neonatol 2011; 215: 199–204

Purpose: The aim of this study was to determine the quality of intrapartum uterine activity (UA) monitoring in daily practice during the first and second stages of labour. The total duration of inadequate UA monitoring is quantified in relation to the technique applied, namely, external tocodynamometry (TOCO) or electrohysterography (EHG).

Material and Methods: 144 UA recordings, collected from deliveries at the Marien-Hospital Witten, Germany, were analysed by obstetricians based at different centres. The included recordings were from singleton and simultaneously with external TOCO and EHG monitored pregnancies. External TOCO and EHG UA recordings were blinded.

Results: The percentages of “ adequate ” UA recordings in the first and second stages of labour were much higher for the external EHG than the external TOCO mode (p < 0.001). All doctors evaluated the UA assessment as “ easier ” (p < 0.001) using the EHG compared with TOCO .

Conclusion: Intrapartum UA monitoring in daily practice via the EHG mode provides a more recognisable UA trace than the TOCO.

2011

Home Labour Induction with Retrievable Prostaglandin Pessary and Continuous Telemetric Trans-Abdominal
Fetal ECG Monitoring

Zubair Rauf, Ediri O’Brien, Tamara Stampalija, Florin P. Ilioniu, Tina Lavender, Zarko Alfirevic

PLoS ONE 6(11): e28129. doi:10.1371/journal.pone.0028129

Objective: To evaluate the feasibility of continuous telemetric trans-abdominal fetal electrocardiogram (a-fECG) in women undergoing labour induction at home.

Study Design: Low risk women with singleton term pregnancy undergoing labour induction with retrievable, slow-release dinoprostone pessaries (n = 70) were allowed home for up to 24 hours, while a-fECG and uterine activity were monitored in hospital via wireless technology. Semi-structured diaries were analysed using a combined descriptive and interpretive approach.

Results: 62/70 women (89%) had successful home monitoring; 8 women (11%) were recalled because of signal loss. Home monitoring lasted between 2–22 hours (median 10 hours). Good quality signal was achieved most of the time (86%, SD 10%). 3 women were recalled back to hospital for suspicious a-fECG. In 2 cases suspicious a-fECG persisted, requiring Caesarean section after recall to hospital. 48/51 women who returned the diary coped well (94%); 46/51 were satisfied with home monitoring (90%).

Conclusions: Continuous telemetric trans-abdominal fetal ECG monitoring of ambulatory women undergoing labour induction is feasible and acceptable to women.

2011

Intrapartum External Fetal Monitoring in Obese Women

Rauf.  Z,  Ommani. S,  Payne. B,  Brown. R,  Hassan. S,  Hayes-Gill. B R,  Cohen. W,  Alfirevic. Z

Paper presented at

The Perinatal Medicine 2011

15-17 June 2011

Harrogate International Centre, UK

Objectives:  To evaluate the success of intrapartum external fetal monitoring in obese women.

Methods: Group 1 ( Liverpool Women’s Hospital): A retrospective analysis of data for 400 labouring women with singleton pregnancies at ≥37+0 weeks gestation, stratified into four BMI groups (<30, 30-34.9, 35-39.9; ≥40). For each group we calculated the rate of suboptimal CTG recordings defined as the need for fetal scalp electrode (FSE).

Group 2 (Temple University Hospital Pennsylvania & Queens University Hospital New York)

19 obese women simultaneously monitored in labour with Doppler ultrasound (conventional external CTG), FSE (internal CTG-FSE) and wireless external abdominal fetal (aECG) monitoring device (MONICA AN24).

Reliability was assessed with Positive Percent Agreement defined as the percentage of the time when external fetal monitoring (aECG or CTG) gave an interpretable trace within 10% of the value reported by FSE.

Results: Conventional external CTG monitoring in women with high BMI was associated with high percentage of labours requiring FSE monitoring (2% for BMI<30, 23% for BMI 30-34.9; 32% for BMI 35-39.9; and 45% for BMI>40).

When FSE recordings from 19 labouring women with BMI >35 were compared with simultaneously obtained aECG and external CTG recordings, the Positive Percent Agreement was 88.4% for aECG and 68.7% for the CTG.

Conclusion: The external ECG monitoring with Monica AN24 may provide a useful alternative to Doppler CTG for women with high BMI.

2011

Function organization of extracardial effects on the fetus cardiac rhythm and studies of their formation during the antenatal development

Gudkov.GV, Pustovaya.JN, Turichenko.O,

Kuban state medical university, Krasnodar, Russia

19.12.2011

http://vestnik.kmldo.ru/archive/18/

Results obtained allowed to recommend for using in obstetrics the new technologies for fetus cardiac rhythm variable till the moment of sonography visualization of systole (10-12 weeks). The EGK halter using allowed to perform the cardiotokographic studies in earlier gestation periods (from 20-23 weeks vs 28-30 weeks in routine CTG), to obtain the additional information about cardiac oxygenation by morphologic analysis of bioelectrical cardiac activity. The data obtained combined with literature data suggested that fetus cardiac monitoring in earlier gestation periods revealed the studies of physiological development of its adaptative-regulatory systems and to diagnose the feto-placentar disturbances.

2010

Bhogal.K, Reinhard.J
British Journal of Midwifery. Vol 18, No, 7: 424-428. July 2010

2010

Maternal Body Mass Index Does Not Affect Performance of Fetal Electrocardiography

Graatsma EM, Miller J, Mulder EJ, Harman C, Baschat AA, Visser GH.

The obesity epidemic challenges traditional antenatal fetal heart rate (FHR) monitoring technologies. Doppler signals in particular are attenuated. We sought to evaluate whether the performance of a novel transabdominal fetal electrocardiogram (fECG) device (AN24, Monica Healthcare) is influenced by body mass index (BMI). We performed a prospective observational study of singleton pregnancies (gestational age [GA] 20 to 41 weeks) monitored overnight with fECG. Recording quality ([RQ] %) of both the best hour and the total recording time of the FHR record were related to BMI. Two hundred four women were monitored. BMI ranged from 16.0 to 50.7 (median BMI 26.9). The correlation coefficient (with 95% confidence interval [CI]) between BMI and RQ was -0.35 (CI -0.60; -0.03) for the gestational age group 20(+0) to 25(+6) weeks, -0.08 (CI -0.28; 0.13) for GA 26(+0) to 33(+6) weeks, and -0.20 (CI -0.40; 0.03) for GA group > or =34(+0) weeks. Median RQ in obese women (BMI > or =30 kg/m(2)) was 97.4, 98.9, and 100%, respectively. BMI has no clinically significant influence on recording quality of FHR monitored with fECG. It can therefore be considered a good method for monitoring the fetal condition in pregnancies of obese women

2010

Comparison of non-invasive fetal electrocardiogram to Doppler cardiotocogram during the 1st stage of labor

Reinhard. J,  Hayes-Gill. B, Yi. Q,  Hatzmann. H, Schiermeier. S

J. Perinat. Med. 38 (2010) 179–185

Abstract

Objective: We compared a non-invasive fetal electrocardiogram (fECG) to Doppler cardiotocogram (CTG) during the 1st stage of labor. Study design: This was a prospective observational study of non-invasive fECG using five abdominal electrodes and one Doppler ultrasound probe in 27 patients. Data were analyzed for reliability, clinical and statistical equivalence. Results: The fECG was similar to the traditional Doppler method. The fECG characterizes a fetal heart rate (FHR) trace in a similar way with regards to acceleration count, decelerations count and coincidence, variability and baseline. The FHR was overall correlated (Pearson’s rs0.91). Conclusion: This non-invasive fECG presents an alternative, reliable and accurate assessment for fetal well-being during the 1st stage of labor.

2009

Introduction:
Unexpected intrauterine fetal death in late gestation has been repeatedly reported in women with OC. This could be a consequence of altered cardiac conduction, presumably induced by increased bile acid concentration (BAC).

Methods: FHR was derived from the RR interval. The trans-abdominal fetal e.c.g. was acquired over ~12h using a Monica AN24 FHR monitor. The short term variability (STV) was calculated according to Dawes and Redman based on the 3.75second FHR averages. The root mean square of successive difference (RMSSD), a measure of true beat-to-beat variability, was also calculated. Data are summarised as mean ± s.d. or median [IQR].

Results and Discussion: Technically-satisfactory recordings of the fetal e.c.g. were obtained from 17 women with OC (pruritus with serum BAC >14μmol/L or ALT >100U/L) and 17 women with uncomplicated pregnancies (NP).
We believe this to be the first time that a link has been observed between raised BAC and an alteration in an index of fetal vagal cardiac control, the RMSSD. The ability to record the beat-to-beat fetal e.c.g. transabdominally with the very small Monica AN24 monitor has allowed us to record for up to 16 hours overnight, with minimal maternal inconvenience.

Comment: This will facilitate the identification of subtle changes in FHR variability and could reduce or abolish the need for alternate day use of antenatal cardiotocography in women with OC.

2009

Objective: Validation of electrohysterography (EHG) as a method for uterine activity monitoring during labour by comparing with intra-uterine pressure catheter (IUCP) recordings. Prospective observational study. Population of the study was thirty-two women in labour, simultaneous recording of uterine activity with EHG and IUCP for at least 30 min.

Results: EHG detects uterine contractions accurately.

Conclusion: EHG detects uterine contractions accurately during labour but the contraction’s characteristics it measures are directly comparable with that of IUCP.

2009

2009

Signal Quality of Non-Invasive Foetal Electrocardiogram (ECG) During Labour

J. Reinhard1, B. R. Hayes-Gill2, Q. Yi3, H. Hatzmann1, S. Schiermeier1

1 Universität Witten/Herdecke, Akademisches Lehrkrankenhaus der Ruhr-Universität Bochum, Frauenheilkunde,
Marien-Hospital Witten
2 School of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham,
NG7 2 RD, United Kingdom
3 Monica Healthcare Ltd, Biocity, Pennyfoot Street, Nottingham, NG1 1GF, United Kingdom

Geburtsh Frauenheilk 2009; 69: 1–5
 

Introduction: During labour non-invasive foetal heart rate monitoring is a routine method for the assessment of foetal well-being. This study examines an alternative assessment by foetal ECG during labour.

Materials and Methods: 32 pregnant women admitted for delivery gave informed consent and were connected to the Monica AN24™. Foetal and maternal ECG signals, noise and patient satisfaction were evaluated during the 1st and 2nd stages of labour.

Results: The median gestational age was 40 weeks (range 34–42). The women had a median BMI of 28.4 (range 24.0–49.5) and the medianbirth weight was 3400 g (range 1915–4470 g). The median total recording time was five hours and 18 minutes (range 38 minutes – 74 hours and 6 minutes). There was a statistical increase of noise from the beginning of the 1st stage of labour to the end of 1st stage of labour (p = 0.03) and until the end of the 2nd stage (p = 0.025). However, foetal and maternal ECG signal quality remained constant throughout labour. No correlation was identified between foetal and maternal ECG, noise and BMI as well as foetal birth weight.

Conclusion: The results show that foetal and maternal ECG signal stays constant throughout labour. Even though noise significantly increases throughout labour, especially during the crowning phase, the foetal and maternal ECG signal can still be differentiated.

2008

NON-INVASIVE TRANSABDOMINAL MONITORING OF FECG AND UTERINE CONTRACTIONS IN SECOND HALF OF GESTATION
M. Graatsma, E. Mulder, L. van Egmond, G. Visser
University Medical Center Utrecht, Perinatology & Gynaecology, Utrecht, Netherlands

Abstract 90

THE JOURNAL OF MATERNAL-FETAL & NEONATAL MEDICINE
VOLUME 21 SUPPLEMENT 1 SEPTEMBER 2008
BOOK OF ABSTRACTS XXI European Congress of Perinatal Medicine
Istanbul, Turkey September 10–13, 2008

2008

2008

Obesity in Obstetrics, New Challenges and Solutions Using Abdominal Fetal ECG

Karnie Bhogal RM RGN, Clinical Specialist Monica Healthcare, Dr. Indu Asanka Jayawardane, Research Fellow Nottingham City Hospital

Midwives

Journal of the Royal College of Midwives

Dec 2008/Jan 2009

2008

Foetal electrocardiogram (EKG) is an alternative to Doppler ultrasound cardiotocogram (CTG) for antenatal assessment of foetal well-being – preliminary results

J.Reinhard, H. Hatzmann, S. Schiermeier
Frauenklinik der Universität Witten/Herdecke, Marien-Hospital, 58452 Witten


Zeitschrift für Geburtshilfe und Neonatologie (Z Geburtsh Neonatol) (In Press)

Abstract - English

Introduction
Computer analysing software is required for assessment of CTGs, because of the low sensitivity and high intra- and interobserver variability. The German Society of Gynaecology and Obstetrics advices using computer analysing CTG software. This study is aimed at evaluating the use of a new foetal EKG analysis system as an alternative to the traditional Doppler ultrasound CTGs in the setting of a university labour suite.
Materials and Methods
10 pregnant women after 32nd weeks’ gestation, who were admitted to hospital and gave informed consent to this study, were connected to the foetal EKG monitor system Monica AN24TM. Patient satisfaction, maternal and foetal EKG detection rates and time required to connect the patient were evaluated.
Results
8 out of 10 women would prefer the Monica AN24TM monitor system than the traditional Doppler ultrasound CTG. In total mean foetal EKG detection rate was 62.3% (SD ± 30.4) during the recorded time interval; at rest detection rate was 75.3% (SD ± 33.2); during night time (23:00 to 07:00) detection rate was 78.3% (SD ± 25.4); during night time and at rest detection rate was 82.2% (SD ± 24.3). Mean recorded time interval was 6 hours and 54 minutes (SD ± 2 hours and 43 minutes). In total maternal EKG detection rate was at 99.7% (SD ± 0.4). Mean time required applying the Monica AN24TM monitor system was 3.2 minutes (SD ± 0.6).
Conclusion
Foetal EKG monitor system may be a good alternative to Doppler ultrasound CTGs. With perspective to analyse beat to beat of foetal EKG heart rates this new monitor system should be superior to Doppler ultrasound CTGs, however further larger studies are needed to confirm this hypothesis.
Key words: Foetal electrocardiogram (EKG), Doppler ultrasound cardiotocogram (CTG), antenatal assessment

Abstract - German

Einleitung
Wegen der niedrigen Spezifität des CTGs und der hohen Intra- und Interobservervariabilität wird der Einsatz additiver Überwachungsmethoden gefordert. Die computergestützte CTG-Analyse wird in den Leitlinien der DGGG empfohlen. In dieser Studie soll die Alternative einer antepartualen fetalen EKG Überwachung in einer geburtshilflichen Abteilung geprüft werden.
Material und Methode
Bei 10 Schwangeren die aus unterschiedlichen Gründen vor der Geburt(nach der 32. SSW), stationär aufgenommen wurden und nach entsprechender Aufklärung der Studie zustimmten, wurde das Monica AN24TM-Überwachungssystem angeschlossen. Patientenzufriedenheit, fetale EKG Detektion und Anlegezeit des AN24 TM wurden ausgewertet.
Ergebnisse
8 von 10 Schwangeren präferierten das neue AN24® im Vergleich zum CTG. Die fetale EKG-Überwachungsfrequenz war im Durchschnitt in 62,3% (SD ± 30,40) der Überwachungszeit möglich, in Ruhe 75,3% (SD ± 33,2), während der Nacht (23:00 bis 07:00) in 78,3% (SD ± 25,4), sowie bei Ruhe nachts in 82,2% (SD ± 24,3). Die Durchschnittszeit der fetalen Ableitung lag bei 6 Stunden und 54 Minuten (SD ± 2 Stunden und 43 Minuten). Insgesamt betrug die mütterliche EKG-Detektionsrate 99,7% (SD ± 0,40). Die Anlegezeit der Elektroden und des Monica AN24TM Systems betrug im Durchschnitt 3,2 Minuten (SD ± 0,6).
Schlussfolgerung
Die fetale EKG-Überwachung kann in der modernen Schwangerenüberwachung eine Alternative zum CTG sein. Das fetale EKG ist durch die Möglichkeit einer Analyse einer Schlag-zu-Schlag-Variabilität des fetalen Herzschlags dem Doppler CTG überlegen. Vor allem auch intrapartual und bei besonderen Fragestellungen sind weitere Studien zur Effektivität des Verfahrens erforderlich.
Schlüsselwörter: fetales Elektrokardiogramm (EKG), Doppler-Kardiotokografie (CTG), antepartualen Überwachung

2008

Fetal electrocardiography: feasibility of long-term fetal heart rate recording

The feasibility and accuracy of long-term transabdominal fetal electrocardiogram (fECG) recordings throughout pregnancy were studied using a portable fECG monitor. Fifteen-hour recordings of fetal heart rate (FHR) were performed in 150 pregnant women at 20–40 weeks of gestation and 1-hour recordings were performed in
22 women in labour and compared with simultaneous scalp electrode recordings. When ‡60% of fECG signals was present, the recording was defined as good. Eighty-two percent (123/150) of antenatal recordings were of good quality. This percentage increased to 90.7 (136/150 recordings) when only the night part (11 p.m.–7 a.m.) was considered. Transabdominal measurement of FHR and its variability correlated well with scalp electrode recordings (r = 0.99, P < 0.01; r = 0.79, P < 0.01, respectively). We demonstrated the feasibility and accuracy of long-term
transabdominal fECG monitoring.

2008

Non-invasive detection of significant uterine activity

American Journal of Obstetrics and Gynecology, Volume 199, Issue 6, Pages S225-S225

J. Miller, K. Ty-Torredes, M. Schindel, C. Harman, A. Baschat

OBJECTIVE: Intrapartum monitoring of uterine contractions with an
intrauterine pressure catheter (IUPC) invasively provides direct evidence of
contraction frequency and strength but is neither without risk nor available for
all patients. We sought to determine if uterine electromyography (EMG) using
the AN24 (Monica Healthcare, Nottingham, UK) reliably detects contractions.

STUDY DESIGN: Prospective observational study of laboring patients
monitored with an IUPC and the AN24 simultaneously. Only good quality IUPC
contractions with clear baseline and contour were used for comparison.
Contractions were matched between the two devices and measurements were
taken in mmHg or mV as indicated at 5 points-baseline at beginning and end,
peak, and midway along the upstroke and downstroke. Peak contraction values
were correlated and a ROC curve was constructed.

RESULTS: 297 IUPC contractions were measured in 17 patients (range 5-20,
median 20). The AN24 detected an additional 5 contractions not documented
by the IUPC. Overall correlation between mmHg and mV was Pearson 0.644,
p<0.0001 and the relationship between the two was best expressed by a 3rd
order polynomial regression graph (F=628.170, r 0.455). The polynomial fit
was due to differences in the correlation at different contraction strengths:
<50 mmHg (Pearson 0.531, linear fit F=396.829, r2 0.282, all p<0.0001) and
>50 mmHg (Pearson 0.333, linear fit F=61.784, r2 0.111, all p<0.0001).
Using a cutoff of 99.0 mV, contraction intensity in excess of Braxton-Hicks
contractions are detected with 70.5% sensitivity and 74.5% specificity (ROC
AUC 0.826 95%CI 0.806-0.857, p<0.0001).

CONCLUSION: The AN24 is a non-invasive monitor with the capability to
distinguish meaningful contractions from Braxton-Hicks.

2007

OBJECTIVE: Non-invasive fetal heart rate (FHR) monitoring using the fetal-ECG signal as obtained from the maternal abdomen has the advantage of obtaining prolonged recordings, when compared to FHR monitoring using ultrasound.

RESULTS: When total recording time was considered, 103/120 (86%) recordings were of good quality. This percentage increased to 92% (111/120 recordings) when only the night part (11pm-7am) was considered. Lower recording quality was obtained at 26-28 weeks (73%).
CONCLUSION: We demonstrated the feasibility of a renewed fetal monitoring technique. Recording quality was optimal during the 8-hours overnight recording. In the future, continuous FHR monitoring with the non-invasive fECG monitor can be of additional value in high-risk pregnancies. Recordings can be performed in both the clinical and home environment.