Fluid-structure-growth modeling of the ageing aorta in humans: biomechanical and hemodynamic consequences of elastin degradation

Elastin is, together with collagen, one of the key proteins within the wall of the aorta. It allows the aorta to distend, facilitating the ejection of blood from the heart and ensuring optimal hemodynamic conditions. Unfortunately, elastin is deposited only during early life and the elastin that an individual is born with, will serve for his/her entire lifetime. This is in contrast with collagen and other constituents of the aortic wall, which have a natural turnover rate with a permanent breakdown of existing and deposition of new material. As we grow from a baby to an adult person, the elastin gets stretched and introduces a kind of pre-tension in the aorta (comparable to the function of steel in pre-stressed concrete). With age, the elastin progressively degrades (at the age of 40, about half of the elastin is no longer intact) leading to an increased tortuosity of arteries and progressive dilatation. The aim of this research project is to build a so-called fluid-solid-growth computer model of the human aorta that will allow us to predict the consequences of this ageing process on the mechanical stresses and stretch of the aortic wall, and how this affects blood pressure and blood flow. This type of model can subsequently be used when developing computer models of individual patients that allow to predict how the aorta of this patient will respond to surgical interventions, such as the placement of a prosthesis.