Mechanical characterization of arteries affected by fetal growth restriction in guinea pigs (Cavia porcellus)

Abstract

Fetal growth restriction (FGR) is a perinatal condition associated with a low birth weight that results mainlyfrom maternal and placental constrains. Newborns affected by this condition are more likely to develop in thelong term cardiovascular diseases whose origins would be in an altered vascular structure and function definedduring fetal development. Thus, this study presents the modeling and numerical simulation of systemic vesselsfrom guinea pig fetuses affected by FGR. We aimed to characterize the biomechanical properties of the arterialwall of FGR-derived the aorta, carotid, and femoral arteries by performing ring tensile and ring opening testsand, based on these data, to simulate the biomechanical behavior of FGR vessels under physiological conditions.The material parameters were first obtained from the experimental data of the ring tensile test. Then, the residualstresses were determined from the ring opening test and taken as initial stresses in the simulation of thering tensile test. These two coupled steps are iteratively considered in a nonlinear least-squares algorithm toobtain the final material parameters. Then, the stress distribution changes along the arterial wall under physiologicalpressure were quantified using the adjusted material parameters. Overall, the obtained results providea realistic approximation of the residual stresses and the changes in the mechanical behavior under physiologicalconditions.