"Fetal hearts in other mammals such as pigs, which we have been using as models, show such an organisation even early in gestation, with a smooth change in cell orientation going through the heart wall. But what we actually found is that such organisation was not detectable in the human fetus before 20 weeks," she said.
Professor Arun Holden, from The University of Leeds' School of Biomedical Sciences, said: "The development of the fetal human heart is on a totally different timeline, a slower timeline, from the model that was being used before. This upsets our assumptions and raises new questions. Since the wall of the heart is structurally disorganised, we might expect to find arrhythmias, which are a bad sign in an adult. It may well be that in the early stages of development of the heart arrhythmias are not necessarily pathological and that there is no need to panic if we find them. Alternatively, we could find that the disorganisation in the tissue does not actually lead to arrhythmia."
A detailed computer model of the activity and architecture of the developing heart will help make sense of the limited information doctors can obtain about the fetus using non-invasive monitoring of a pregnant woman.
Professor Holden said: "It is different from dealing with an adult, where you can look at the geometry of an individual's heart using MRI (Magnetic Resonance Imaging) or CT (Computerised Tomography) scans. You can't squirt x-rays at a fetus and we also currently tend to avoid MRI, so we need a model into which we can put the information we do have access to."
He added: "Effectively, at the moment, fetal ECGs are not really used. The textbooks descriptions of the development of the human heart are still founded on animal models and 19th century collections of abnormalities in museums. If you
|Contact: Emma Thorne|
University of Nottingham