Chiara Colombo

One-dimensional (1D) cardiovascular models have become increasingly important as a means of accurately simulating the behavior of the human cardiovascular system (CVS) under both healthy and pathological conditions. Nowadays, some 1D models comprise detailed descriptions of arterial and venous networks. Furthermore, these models incorporate geometrical multiscale physiological processes by utilizing lumped-parameter (0D) models that provide a comprehensive description of complex aspects of the CVS, including but not limited to cardiac function, microcirculation connecting arteries to veins, valve dynamics, and the closing of the CVS loop. Despite the usefulness of these models, it is worth noting that most of them do not consider the effects of orthostatic stress (gravity) on the CVS. This is because most of these models are designed for the supine position, which is not representative of a number of real-life scenarios in which gravity significantly affects cardiovascular function. Therefore, more sophisticated models that incorporate the effects of gravity and other external factors on the CVS need to be developed to more accurately represent cardiovascular dynamics in different postures and during different physical activities.

Our goal is to extend the global multiscale 1D-0D cardiovascular model proposed by Müller et al. [1] by incorporating the effects of gravity. We want to develop a cardiovascular model that can accurately reproduce the most important physiological processes, both healthy and pathological, in response to postural changes.

The research will involve an in-depth analysis of the literature on the topic, improvements of mathematical models, development of numerical schemes, analysis of experimental data to parametrize and eventually further develop models and a final clinical application using the new features implemented in the cardiovascular model.

The extended model could be used to compare the solutions obtained with our model to some relevant physiological parameters, and to investigate pathological conditions such as hypertension and orthostatic intolerance. It will serve as a valuable tool to expand our understanding of the CVS and the impact of gravity on its function.

[1] Müller L.O., Watanabe S.M., Toro E.F., Feijóo R.A., and Blanco P.J., “An anatomically detailed arterial-venous network model. Cerebral and coronary circulation”, submitted for publication in Front., (2023).