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Fetal Electrocardiogram (fetal + electrocardiogram)
Selected AbstractsMethods for prenatal assessment of fetal cardiac functionPRENATAL DIAGNOSIS, Issue 13 2009Tim Van Mieghem Abstract Fetal cardiac function is increasingly recognized as a marker of disease severity and prognosis in selected fetal conditions. Magnetic resonance imaging (MRI) has been used in experimental (animal) fetal cardiology but the lack of a noninvasive fetal electrocardiogram (ECG) to trigger image acquisition remains a major limiting factor precluding its application in humans. Fetal medicine specialists are therefore limited to ultrasound to evaluate human fetal cardiac function. In this review, we aim to provide a complete overview of the different ultrasound techniques that can be used for fetal cardiac function assessment and we discuss their (theoretical) strengths and shortcomings. Conventional methods include M-mode assessment of ventricular contractility and Doppler assessment of the precordial veins and cardiac output (CO). More recent techniques such as the measurement of the myocardial performance index (MPI), myocardial motion analysis with tissue Doppler, speckle tracking and three-dimensional (3D) ultrasound techniques are also discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Fetal heart rate monitoring from maternal body surface potentials using independent component analysisANIMAL SCIENCE JOURNAL, Issue 5 2004Wenxi CHEN ABSTRACT The fetal heart rate is indispensable for monitoring the health of unborn cattle fetuses. To monitor the fetal heart rate, a method employing independent component analysis (ICA) to extract the fetal electrocardiogram (fECG) from potentials measured on the maternal body surface and composed of a mixture of the maternal ECG (mECG), fECG, baseline drift and noise is described. A mixing of the raw data was simplified using a linear time-invariant model. To separate the fECG from the mECG, baseline drift, and noise, an ICA strategy was applied, using a hyperbolic tangent as the contrast function and treating mutual information with the minimization principle to find the optimum demixing matrix to derive the fECG from the measured signals. After the feasibility of this method was shown on simulated signals obtained by randomly mixing pure fECG, pure mECG, low frequency sinusoidal drift and noise, real signals from three cloned pregnant Holstein cows with 157, 177 and 224-day gestation periods were used to verify the separation method. The results show that the fECG, mECG, low-frequency sinusoidal drift and noise can be clearly segregated in simulations, and that the fECG, mECG, baseline drift and noise can be successfully derived from real signals. The ICA approach has great potential in effectively detecting the fECG from maternal body surface potentials. [source] Inter- and intra-observer agreement of intrapartum ST analysis of the fetal electrocardiogram in women monitored by STANBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 4 2009MEMH Westerhuis Objective, The objective of this study was to quantify inter- and intra-observer agreement on classification of the intrapartum cardiotocogram (CTG) and decision to intervene following STAN guidelines. Design, A prospective, observational study. Setting, Obstetrics Department of a tertiary referral hospital. Population, STAN recordings of 73 women after 36 weeks of gestation with a high-risk pregnancy, induced or oxytocin-augmented labour, meconium-stained amniotic fluid or epidural analgesia. Methods, Six observers classified 73 STAN recordings and decided if and when they would suggest an intervention. Proportions of specific agreement (Ps) and kappa values (K) were calculated. Main outcome measures, Agreement upon classification of the intrapartum CTG and decision to perform an intervention. Results, Agreement for classification of a normal and a (pre)terminal CTG was good (Ps range 0.50,0.84), but poor for the intermediary and abnormal CTG (Ps range 0.34,0.56). Agreement on the decision to intervene was higher, especially on the decision to perform ,no intervention' (Ps range 0.76,0.94). Overall inter-observer agreement on the decision to intervene was considered moderate in five of six observer combinations according to the kappa (K range 0.42,0.73). Intra-observer agreement for CTG classification and decision to intervene was moderate (K range 0.52,0.67 and 0.61,0.75). Conclusions, Inter-observer agreement on classification of the intrapartum CTG is poor, but addition of information regarding fetal electrocardiogram, especially in case of intermediary or abnormal CTG traces, results in a more standardised decision to intervene. [source] Fetal electrocardiography: feasibility of long-term fetal heart rate recordingsBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 2 2009EM Graatsma 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. [source] Changes in the ST-interval segment of the fetal electrocardiogram in relation to acid,base status at birthBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 13 2008M Melin Objective, To assess the occurrence of ST-interval segment changes of the fetal electrocardiogram (ECG) and cardiotocographic (CTG) abnormalities preceding acidaemia at birth. Design, Case,control study. Setting, University hospital labour ward. Sample, Newborns with severe cord artery metabolic acidaemia (pH < 7.00 and lactate , 10 mmol/l; n= 24), moderate metabolic acidaemia (pH 7.00,7.09 and lactate , 10; n= 48), acidaemia (pH 7.00,7.09; n= 52), pre-acidaemia (pH 7.10,7.19; n= 265), and controls (pH , 7.20; n= 117). Methods, Monitoring traces were assessed blinded to outcome. Main outcome measures, CTG and ST changes. Results, Any ST event occurred significantly more often among cases with severe (79%) and moderate (75%) metabolic acidaemia than among controls (50%). The difference was restricted to baseline T/QRS rises and to the second stage of labour, during which any event only occurred significantly more often among cases with severe metabolic acidaemia (62%) than among controls (38%). ST events coincided with abnormal CTG patterns in 67, 44, 40, and 28% of cases with severe and moderate metabolic acidaemia, acidaemia, and pre-acidaemia, respectively, and in 12% of controls. ST events with intermediary CTG were similarly frequent in the case groups (0,6%) as in the controls (4%). The ST guidelines stated intervention in 96, 62, 73, and 49% of case groups and 23% of controls. Conclusions, Only two of three cases with severe and less than half of cases with moderate metabolic acidaemia were preceded by ST events coinciding with CTG abnormalities. It is therefore important to intervene for long-lasting, rapidly deteriorating or marked (preterminal) CTG abnormalities, also in the absence of ST events. [source] | ||||||||||