Jalali Ali, Jones Gerard F, Licht Daniel J, Nataraj C
Department of Mechanical Engineering, Villanova University, Villanova, PA 19085, USA.
Neurovascular Imaging Lab, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
Biomed Res Int. 2015;2015:987293. doi: 10.1155/2015/987293. Epub 2015 Oct 25.
This paper is concerned with the mathematical modeling of a severe and common congenital defect called hypoplastic left heart syndrome (HLHS). Surgical approaches are utilized for palliating this heart condition; however, a brain white matter injury called periventricular leukomalacia (PVL) occurs with high prevalence at or around the time of surgery, the exact cause of which is not known presently. Our main goal in this paper is to study the hemodynamic conditions under which HLHS physiology may lead to the occurrence of PVL. A lumped parameter model of the HLHS circulation has been developed integrating diffusion modeling of oxygen and carbon dioxide concentrations in order to study hemodynamic variables such as pressure, flow, and blood gas concentration. Results presented include calculations of blood pressures and flow rates in different parts of the circulation. Simulations also show changes in the ratio of pulmonary to systemic blood flow rates when the sizes of the patent ductus arteriosus and atrial septal defect are varied. These changes lead to unbalanced blood circulations and, when combined with low oxygen and carbon dioxide concentrations in arteries, result in poor oxygen delivery to the brain. We stipulate that PVL occurs as a consequence.
本文关注一种严重且常见的先天性缺陷——左心发育不全综合征（HLHS）的数学建模。手术方法被用于缓解这种心脏疾病；然而，一种名为脑室周围白质软化（PVL）的脑白质损伤在手术时或手术前后的发生率很高，其确切原因目前尚不清楚。本文的主要目标是研究HLHS生理状况可能导致PVL发生的血流动力学条件。已开发出HLHS循环的集总参数模型，并整合了氧气和二氧化碳浓度的扩散模型，以研究诸如压力、流量和血气浓度等血流动力学变量。给出的结果包括循环不同部位的血压和流速计算。模拟还显示，当动脉导管未闭和房间隔缺损的大小时，肺循环与体循环血流速率之比会发生变化。这些变化会导致血液循环失衡，再加上动脉中低氧和二氧化碳浓度，会导致大脑的氧气输送不足。我们推测PVL就是由此产生的。
