A simple multi-scale model to evaluate left ventricular growth laws

Cardiac growth is the natural capability of the heart of
adapting to changes in blood flow demands. Cardiac diseases can trigger
the same process leading to an abnormal type of growth. Although
several models have been published, details on this process remain still
unclear. This study offers an analysis on the driving force of cardiac
growth along with an evaluation on the final grown state. Through a
zero dimensional model of the left ventricle we evaluate cardiac growth
in response to three valve diseases, aortic and mitral regurgitation along
with aortic stenosis. We investigate how different combinations of stress
and strain based stimuli affect growth in terms of cavity volume and
wall volume. All of our simulations are able to reach a converged state
without any growth constraint. The simulated grown state corresponded
to the experimentally observed state for all valve disease cases, except
for aortic regurgitation simulated with a mix of stress and strain stimuli.
Thus we demonstrate how a simple model of left ventricular mechanics
can be used to have a first evaluation of a designed growth law.