It is now well known that altered hemodynamics can alter the genes that are expressed by diverse vascular cells, which in turn plays a critical role in the ability of a blood vessel to adapt to new biomechanical conditions and governs the natural history of the progression of many types of disease. Recent advances in molecular and cell biology, in vivo medical imaging, biomechanics, computational mechanics, and computing power provide an unprecedented opportunity to begin to understand such hemodynamic effects on vascular biology, physiology, and pathophysiology. In this work, we present a new computational framework for Fluid-Solid-Growth that brings together recent advances in computational biosolid and biofluid mechanics that can exploit new information on the biology of vascular growth and remodeling as well as in vivo patient-specific medical imaging so as to enable realistic simulations of vascular adaptations, disease progression, and clinical intervention.
The figure shows the iterative loop and information transferred in the coupling between the fluid-structure interactions (FSI) and growth and remodeling (G&R) parts of a fluid-solid-growth (FSG) framework. The FSI computation describes the hemodynamic state of the artery over the short timescale (seconds). Then, we identify the biomechanical stimuli (in this case, tensile stress and wall shear stress) that elicit a G&R response. The G&R computation describes the evolution of vessel wall geometry, composition, and material properties over the long timescale (weeks to months). Once the vessel changes significantly in geometry and/or mechanical properties, we define a new linearized geometry, pre-stress, and material properties for the FSI computation.
References:
- “Computational Simulations of Hemodynamic Changes within Thoracic, Coronary, and Cerebral Arteries Following Early Wall Remodeling in Response to Distal Aortic Coarctation.” Biomechanics and Modeling in Mechanobiology. DOI: 10.1007/s10237-012-0383-x
. - “A Computational Framework for Coupled Fluid-Solid Growth in Cardiovascular Simulations.” Computer Methods in Applied Mechanics and Engineering Vol. 198, pp. 3583-3602.