title: Normal ranges for fetal electrocardiogram values for the healthy fetus of 18-24 weeks of gestation: a prospective cohort study.
abstract: The fetal anomaly ultrasound only detects 65 to 81 % of the patients with congenital heart disease, making it the most common structural fetal anomaly of which a significant part is missed during prenatal life. Therefore, we need a reliable non-invasive diagnostic method which improves the predictive value for congenital heart diseases early in pregnancy. Fetal electrocardiography could be this desired diagnostic method. There are multiple technical challenges to overcome in the conduction of the fetal electrocardiogram. In addition, interpretation is difficult due to the organisation of the fetal circulation in utero. We want to establish the normal ranges and values of the fetal electrocardiogram parameters in healthy fetuses of 18 to 24 weeks of gestation.
  
  
  
  Women with an uneventful singleton pregnancy between 18 and 24 weeks of gestation are asked to participate in this prospective cohort study. A certified and experienced sonographist performs the fetal anomaly scan. Subsequently, a fetal electrocardiogram recording is performed using dedicated signal processing methods. Measurements are performed at two institutes. We will include 300 participants to determine the normal values and 95 % confidence intervals of the fetal electrocardiogram parameters in a healthy fetus. We will evaluate the fetal heart rate, segment intervals, normalised amplitude and the fetal heart axis. Three months postpartum, we will evaluate if a newborn is healthy through a questionnaire.
  
  
  
  Fetal electrocardiography could be a promising tool in the screening program for congenital heart diseases. The electrocardiogram is a depiction of the intimate relationship between the cardiac nerve conduction pathways and the structural morphology of the fetal heart, and therefore particularly suitable for the detection of secondary effects due to a congenital heart disease (hypotrophy, hypertrophy and conduction interruption).
authors.affiliation: Department of Obstetrics and Gynaecology, Máxima Medical Centre, P.O. box 7777, 5500 MB, Veldhoven, The Netherlands. kimverdurmen@live.nl.
authors.forename: Kim M J
authors.initials: KMJ
authors.lastname: Verdurmen
authors.affiliation: Department of Obstetrics and Gynaecology, Máxima Medical Centre, P.O. box 7777, 5500 MB, Veldhoven, The Netherlands.
authors.forename: Carlijn
authors.initials: C
authors.lastname: Lempersz
authors.affiliation: Faculty of Electrical Engineering, Eindhoven University of Technology, P.O. box 513, 5612 AZ, Eindhoven, The Netherlands.
authors.forename: Rik
authors.initials: R
authors.lastname: Vullings
authors.affiliation: Department of Paediatrics, Máxima Medical Centre, P.O. box 7777, 5500 MB, Veldhoven, The Netherlands.
authors.forename: Christian
authors.initials: C
authors.lastname: Schroer
authors.affiliation: Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
authors.forename: Tammo
authors.initials: T
authors.lastname: Delhaas
authors.affiliation: Department of Obstetrics and Gynaecology, Máxima Medical Centre, P.O. box 7777, 5500 MB, Veldhoven, The Netherlands.
authors.forename: Judith O E H
authors.initials: JOEH
authors.lastname: van Laar
authors.affiliation: Department of Obstetrics and Gynaecology, Máxima Medical Centre, P.O. box 7777, 5500 MB, Veldhoven, The Netherlands.|Faculty of Electrical Engineering, Eindhoven University of Technology, P.O. box 513, 5612 AZ, Eindhoven, The Netherlands.
authors.forename: S Guid
authors.initials: SG
authors.lastname: Oei
mesh_terms: D000328:Adult; D004562:Electrocardiography / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000196:embryology; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D012016:Reference Values; D016216:Ultrasonography, Prenatal / Q000379:methods / Q000706:statistics & numerical data*
keywords: Congenital heart disease; Fetal electrocardiogram parameters; Fetal electrocardiography