Christiane Kähler

The application of fetal magnetocardiography (FMCG) to investigate fetal arrhythmias and congenital heart defects (CHD)

Fetal magnetocardiography (FMCG), a new non‐invasive diagnostic tool in the analysis of the electrophysiological changes of the heart, was selectively applied in cases of fetal arrhythmias and congenital heart defect (CHD) to demonstrate its value for diagnosis and prenatal management.

Maternal and fetal side effects of tocolysis using transdermal nitroglycerin or intravenous fenoterol combined with magnesium sulfate

OBJECTIVE To compare the maternal and fetal side effects of transdermal nitroglycerin and intravenous fenoterol combined with magnesium sulfate in a prospective randomised study. STUDY DESIGN Fifty pregnant women between 27 and 35 weeks of gestation with preterm labour were treated with either nitroglycerin (0.4-0.8 mg/h) or fenoterol (60 - 120 microg/h). Outcome parameters were (1) the effects on fetal and maternal heart frequency (FHF/MHF) and blood pressure, and (2) subjective experiences of adverse effects assessed by utilising a questionnaire. RESULTS In the fenoterol group, elevated mean MHF, FHF and systolic blood pressure were recorded compared to nitroglycerin. Fewer maternal side effects were reported in the nitroglycerin group. Palpitations (82%), tremor (68%) and restlessness (64%) were most common in the fenoterol group (two drop-outs), whereas nitroglycerin caused headaches in 71% of the cases (four drop-outs). CONCLUSION Transdermal nitroglycerin appears to be a safe therapy for the mother and fetus and is a promising new option for the treatment of preterm labour.

Doppler measurements in fetoplacental vessels after maternal betamethasone administration.

Objective: To observe the influence of maternal betamethasone administration for fetal lung maturation on the arterial, venous and intracardiac blood flow of the fetus and the uterine arteries. Methods: Twenty-seven women with singleton pregnancies were examined before the first, and 30 min and 8, 24, 48 and 72 h after the second of two single doses of 8 mg of betamethasone. We recorded blood flow velocity waveforms of the umbilical artery (UA), the middle cerebral artery, the uterine arteries, the ductus venosus, the inferior vena cava and the right hepatic vein, the pulmonary trunk, the ductus arteriosus and the right and left intraventricular inflow of the heart. Results: The resistance index of the UA showed a significant transient decrease 30 min (p = 0.024) after the second betamethasone dose. The peak systolic velocity of the ductus arteriosus increased significantly 30 min after the 2nd dose (p = 0.009) and then returned to non-significant values. No significant change was observed in any of the other vessels. Conclusion: Betamethasone causes short-term changes in fetal blood flow. However, this effect seems to be mild and reversible and does not appear to contraindicate the use of corticosteroids to promote fetal lung maturation.

Fetal magnetoencephalography: a non-invasive method for the assessment of fetal neuronal maturation

Objective To assess the maturation of auditory evoked cortical responses in the human fetus using fetal magnetoencephalography.

Fetal heart rate variability in growth restricted fetuses.

Abstract Intrauterine growth restriction (IUGR) remains a major problem in perinatal medicine because of the variety of its underlying causes and the prediction of its outcome. Characteristics of heartbeat interval patterns are associated with neuro-vegetative and humoral regulatory processes. Fetal magnetocardiography allows non-invasive assessment of these processes with high precision throughout the second half of gestation. The aim of our study was the analysis of linear and non-linear parameters of fetal heart rate fluctuations to distinguish between IUGR fetuses and a cohort of normal subjects, both pre-selected from heart-rate traces representing a quiet state of activity in the third trimester of gestation.

Fetal magnetocardiography in the investigation of congenital heart defects

OBJECTIVES To investigate the changes of the fetal magnetocardiography (FMCG), a new noninvasive diagnostic tool in the analysis of electrophysiologic changes of the heart, in cases of congenital heart defect (CHD). METHODS The FMCG was analysed and compared to the postnatal ECG in eight cases of CHD: atrial septal defect ASDII (three cases), a combination of atrioventricular-septal-defect (AVSD) and Tetralogy of Fallot (TOF) (one case ), complete transposition of great arteries (d-TGA) (two cases), coarctation of aorta (COA) (one case), stenosis of the pulmonary artery (PS) and right ventricular hypoplasia (one case). RESULTS (1) The following FMCG changes were observed: a split R-wave (AVSD/TOF, ASDII), prolongation of QRS complex (COA, PS). (2) The notch of the R-wave could not be observed in the newborn with AVSD/TOF. (3) Neither the fetal FMCG nor the neonatal ECG revealed any changes in the cases of d-TGA. (4) All other neonatal ECGs were corresponding to the FMCG. CONCLUSIONS The FMCG can unearth changes of the cardiac electrophysiologic activity in the case of CHD. The method provides additional information concerning the effect of a CHD on the cardiac conductory system. As in the neonate, the FMCG changes do not reflect the severity of the CHD. FMCG cannot serve as a primary diagnostic tool in the case of CHD as compared to echocardiography.

Prenatal diagnosis of the Wolf‐Parkinson‐White‐syndrome by fetal magnetocardiography

Sir, Blondel et al. have demonstrated the apparent effect on rates of preterm and postterm birth rates when changing from menstrual to early ultrasound dating. Although confidence intervals for the differences in the results of the two methods is not provided in this paper, the large database of over 44,000 is likely to make the confidence intervals very narrow. The authors state that the ultrasound dating was based on the fetal biparietal diameter usually carried out between 16 and 18 weeks but do not tell us which formula was used. No doubt this could have varied between the two centres and over the time of the study. Two commonly used published formulae (Hadlock et al. and Altman and Chitty) differ by 3.5 days for a biparietal diameter measurement of 41 mm (approximately equivalent to 18 weeks of gestation). We have carried out an audit of ultrasound dating in a singleton pregnancy population restricted to those pregnancies with spontaneous onset of labour and delivery of a live healthy infant. In this audit, dating was also based on biparietal diameter, usually between 18 and 20 weeks. The audit has shown that the preterm rate can vary between 1.8% and 3.7% according to the two formulae referred above. This represents a 51% difference. This is another factor that needs to be taken into account when interpreting epidemiological reports on the changes in preterm and postterm births and we recommend that authors publish which dating formula has been used.

Erratum to: Impact of the nitric oxide-donor pentaerythrityl-tetranitrate on perinatal outcome in risk pregnancies: a prospective, randomized, double-blinded trial

On page 1 “adjusted relative risk (RR)“ should be changed to “adjusted odds ratio (OR)”. On page 1, 3 and in the table head of table 2 “adjusted RR” should be changed to “adjusted OR”. On page 3 “Mantel-Haenszel estimates of relative risk” should be changed to “Mantel-Haenszel estimates of odds ratios”. In Table 2, caption b “Mantel-Haenszel estimate of relative risk” should be changed to “Mantel-Haenszel estimate of odds ratio”.

Pentaerythrityltetranitrate (PETN) improves utero- and feto-placental Doppler parameters in pregnancies with impaired utero-placental perfusion in mid-gestation – a secondary analysis of the PETN-pilot trial

Abstract Aim: In pregnancies complicated by impaired utero-placental perfusion, pentaeritrithyltetranitrate (PETN) has been shown to reduce the risk of severe fetal growth restriction (FGR) and perinatal death by 39%. The effect is most likely related to the vasodilatative influence of PETN. To assess its impact on utero-placental and fetal perfusion, we analyzed the Doppler parameters measured during the PETN pilot-trial. Methods: One hundred and eleven pregnancies presenting impaired utero-placental resistance at mid-gestation were included in the trial. Fifty-four women received PETN, while 57 received a placebo. Doppler velocimetry measurements were monitored biweekly. Statistical analysis was performed using a mixed linear model. Results: Within the first week of treatment, the mean pulsatility index (PI) of the uterine artery (UtA) dropped more prominently in the PETN group [−0.20, 95% confidence interval (CI): −0.34 to −0.05, P=0.007). The adjusted relative risk (RR) for abnormal cerebro-placental ratio (CPR) was significantly reduced by PETN [RR 0.412 (95% CI: 0.181–0.941)]. Kaplan-Meier analysis demonstrates the postponement of absent end-diastolic flow (AED), absent or reverse end-diastolic flow (ARED), brain sparing and abnormal cerebroplacental ratio (CPR) in the PETN group. Conclusion: The demonstrated effect of PETN on utero-placental and feto-placental perfusion strengthens the evidence for a positive impact in pregnancies complicated by impaired placental perfusion and might explain the effect on neonatal outcome, as shown in the PETN-pilot trial.

Die extralobare Sequestration einer fetalen Lunge

Summary The extralobar sequestration is a rare pulmonary malformation. An accurate antenatal evaluation is required for a timely therapy and subsequently a good outcome. Here an unusual case of extralobar pulmonary sequestration in a male human fetus is reported. Antenatal ultrasound at 28th week of gestation has revealed a fetal hydrothorax in coexistence with pulmonary hypoplasia and an isolated pulmonary structure. Authors summarise their postnatal findings with special reference to the pathogenesis of an accessory lung. The aim of this report is to define the association of clinical, gross, and histological features of this rare congential malformation in order to improve the antenatal diagnosis. This case indicates that an extralobar pulmonary sequester is not connected to the tracheobronchial tree, and that the arterial as well as the venous blood supply is realised by aberrant systemic vessels. Moreover, histologically revealed dilatations of the normally differentiated terminal airways within the sequester suggest that hyperechogenity can not be a reliable diagnostic criterion. For the accurate assessment of a pulmonary sequestration a detailed antenatal evaluation of both, the arterial and the venous blood supply is essential.