Development of a simplified mathematical model of the human physiome – An application relating to the cardiovascular system

Background & Objective: The overarching aim of this work is to develop a mathematical model of the human physiome as the basis of an electronic teaching tool for clinical pharmacology. The model is intended to simulate physiological functions and the effect of pathological conditions as well as pharmacological interventions over a time course of up to five days for the purposes of providing a teaching tool [1] for clinical practitioners. The development of the submodel for the cardiovascular system (CVS) is presented as a preliminary example of this work.

Materials & Methods: Functional relationships between the system components of the CVS were established based on current medical literature [2]. Development of the mathematical model describing these relationships was based on the “BEG” (Box, Einstein & Gelman) principle. That is, the model was kept as simple as possible keeping in mind the intended application and purpose of the final model. Algebraic equations were used to describe the functional relationships at steady state. A series of ordinary differential equations was used to account for time-varying effects on the system components, including the effect of pathologies and drug treatments. Pharmacological effects were differentiated based on the mechanism of action on the system components.

Results & Conclusions: Selected results based on simulations from the CVS submodel will be shown in this presentation. For example, the model is capable of simulating the heart rate, cardiac output and blood pressure in a healthy individual and under the influence of heart failure as well as treatment with beta-blockers.
Further expansion of the model is required to ultimately obtain a simplified, but sufficiently comprehensive mathematical description of the human physiome.

[1] Loke et al. (2011) SimPharm: How pharmacy students made meaning of a clinical case differently in paper- and simulation-based workshops. British Journal of Educational Technology 42(5):865–874.
[2] Levick, R. (2010) An Introduction to Cardiovascular Physiology, 5th Edition, Hodder Arnold, UK.