Ménigault E, Vieyres P, Lepoivre B, Durand A, Pourcelot L, Berson M
Unité INSERM 316, Faculté de Médecine, Tours, France.
Med Biol Eng Comput. 1997 Nov;35(6):715-21. doi: 10.1007/BF02510983.
Study of the cardiovascular system of the human fetus is based on non-invasive measurement methods such as Doppler echography systems. The circulation conditions in fetal vessels are usually evaluated by resistance indices, giving limited physiological information on distal territories such as the placenta or the brain. To enhance the understanding of human fetal haemodynamics, a numerical model of the fetal heart has been developed, using the hydraulic-electric analogy. The model is based on a mechanical hypothesis of parallel functioning of the right and left ventricles, considered to have analogue elastance properties. Their behaviour is equivalent to that of a single ventricle ejecting an equivalent blood volume of 7 ml in the aorta. The characterisation of the equivalent ventricle is based on the determination of a set of four parameters (Emax, Vo, kv and Po) representing the maximum ventricle contractility, a reference volume, and volume and pressure constants, respectively. The model proposed is validated by studying the effects of preload and afterload variations on the fetal heart work, and by comparing the numerical results with literature and measured data. The model constitutes the first step towards a global model of the cardiovascular system of the human fetus.
对人类胎儿心血管系统的研究基于非侵入性测量方法，如多普勒超声系统。胎儿血管中的循环状况通常通过阻力指数来评估，这提供的关于胎盘或大脑等远端区域的生理信息有限。为了增强对人类胎儿血液动力学的理解，利用水力 - 电类比法开发了一个胎儿心脏的数值模型。该模型基于左右心室平行运作的力学假设，认为它们具有类似的弹性特性。它们的行为等同于一个单一心室向主动脉射出7毫升等量血液的行为。等效心室的特性基于一组四个参数（Emax、Vo、kv和Po）的确定，分别代表最大心室收缩力、参考体积以及体积和压力常数。通过研究前负荷和后负荷变化对胎儿心脏工作的影响，并将数值结果与文献和测量数据进行比较，对所提出的模型进行了验证。该模型是迈向人类胎儿心血管系统整体模型的第一步。
