The development of a physiological simulation system for the human circulatory system coupling macro and micro models

Abstract

AbstractThis paper describes the development of a physiological simulation model which couples macro and micro models of the biological circulatory system. The macro model for the circulatory system is composed of modules for physiological functions such as neural activity, hormonal adjustment, and body temperature control, and provides a mathematical representation of comprehensive knowledge of systemic circulation physiology. The micro model of the circulatory system, on the other hand, uses differential equations to describe hemodynamics with the heart as a pump, and calculates the systemic hemodynamics produced by heart pulsations in millisecond time steps. An electrical circuit model is constructed for the systemic and pulmonary circulatory systems, in which the time‐varying elasticity of the ventricular muscle corresponds to a variable capacitor. By connecting the macro and micro models through common variables, a simulation which combines macroscopic and microscopic hemodynamics is produced, making it possible to investigate the response of the pulsatile blood flow as various parameter values of the whole circulation system are varied. © 2005 Wiley Periodicals, Inc. Syst Comp Jpn, 36(3): 27–41, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20135