Numerical Models of the Cardiovascular System

The vascular network is composed by arteries, veins and capillaries, each one with different anatomic characteristics and functions. Modelling of the vascular system can be made in different ways, e.g. by describing the feature of vase and its interaction with the fluid that crosses it, and representing particular subsystems or entire systems (arterial tree). The complexity of the model depends on the context in which it must be used. For example if the scope of the analysis is to study the motion of the blood inside the capillaries, it is necessary to know the diameter of these ones, to represent the interaction between the wall of a capillary and red globules. In this way it is possible to obtain a distributed parameters model in which it is necessary to take into account the discontinue nature of the blood vase. Otherwise, if the network of the capillaries is a part of the model of the entire systemic section, this can simply be represented by a single resistance. We consider separately the different parts of the vascular system (systemic and pulmonary arterial trees, systemic and pulmonary venous trees, capillaries and the arterioles). In particular we focus our attention on the systemic arterial tree representation. Given its relevance from the physiological point of view, this systemic arterial section has been developed by many researchers. Many simplifying hypotheses have been made that are not possible in the case of the other subsystems.