De Lazzari Claudio, Neglia D, Ferrari G, Bernini F, Micalizzi M, L'Abbate A, Trivella M G
Institute of Clinical Physiology, V.le dell'Università, 11, 00185 Rome, Italy.
Methods Inf Med. 2009;48(2):113-22. doi: 10.3414/ME0539. Epub 2009 Feb 27.
Mathematical modeling of the cardiovascular system is a powerful tool to extract physiologically relevant information from multi-parametric experiments. The purpose of the present work was to reproduce by means of a computer simulator, systemic and coronary measurements obtained by in vivo experiments in the pig.
We monitored in anesthetized open-chest pig the phasic blood flow of the left descending coronary artery, aortic pressure, left ventricular pressure and volume. Data were acquired before, during, and after caval occlusion. Inside the software simulator (CARDIOSIM) of the cardiovascular system, coronary circulation was modeled in three parallel branching sections. Both systemic and pulmonary circulations were simulated using a lumped parameter mathematical model. Variable elastance model reproduced Starling's law of the heart.
Different left ventricular pressure-volume loops during experimental caval occlusion and simulated cardiac loops are presented. The sequence of coronary flow-aortic pressure loops obtained in vivo during caval occlusion together with the simulated loops reproduced by the software simulator are reported. Finally experimental and simulated instantaneous coronary blood flow waveforms are shown.
The lumped parameter model of the coronary circulation, together with the cardiovascular system model, is capable of reproducing the changes during caval occlusion, with the profound shape deformation of the flow signal observed during the in vivo experiment. In perspectives, the results of the present model could offer new tool for studying the role of the different determinants of myocardial perfusion, by using the coronary loop shape as a "sensor" of ventricular mechanics in various physiological and pathophysiological conditions.
心血管系统的数学建模是从多参数实验中提取生理相关信息的有力工具。本研究的目的是通过计算机模拟器重现猪体内实验获得的全身和冠状动脉测量结果。
我们在麻醉的开胸猪身上监测左冠状动脉降支的相位血流、主动脉压力、左心室压力和容积。在腔静脉阻塞前、期间和之后采集数据。在心血管系统的软件模拟器（CARDIOSIM）中，冠状动脉循环在三个平行分支段中进行建模。全身和肺循环均使用集总参数数学模型进行模拟。可变弹性模型再现了心脏的斯塔林定律。
展示了实验性腔静脉阻塞期间不同的左心室压力-容积环和模拟的心脏环。报告了腔静脉阻塞期间体内获得的冠状动脉血流-主动脉压力环序列以及软件模拟器再现的模拟环。最后展示了实验和模拟的瞬时冠状动脉血流波形。
冠状动脉循环的集总参数模型与心血管系统模型能够再现腔静脉阻塞期间的变化，以及体内实验中观察到的血流信号的深刻形状变形。从长远来看，本模型的结果可以通过将冠状动脉环形状作为各种生理和病理生理条件下心室力学的“传感器”，为研究心肌灌注的不同决定因素的作用提供新工具。
