Including layer-specific residual stresses in a tri-layered arterial model demonstrated a uniform distribution of stresses through the wall thickness, whereas neglecting them incorrectly concentrated stresses at the intima.
Residual stresses are crucial in arterial mechanics to guarantee a uniform distribution of stresses through the wall thickness, and neglecting them leads to incorrect interpretation of layer-specific roles.
Abstract The existence of residual stresses in unloaded arteries has long been known. However, their effect is often neglected in experimental studies. Using a recently developed modelling framework, we aimed to investigate the role of residual stresses in the mechanical behaviour of the tri-layered wall of the pig thoracic aorta. The mechanical behaviour of the intact wall and isolated layers of n = 3 pig thoracic aortas was investigated via uniaxial tensile testing. After modelling the layer-specific mechanical data using a hyperelastic strain energy function, the layer-specific deformations in the unloaded vessel were estimated so that the mechanical response of the computationally assembled tri-layered flat wall would match that measured experimentally. Physiological tension–inflation of the cylindrical tri-layered vessel was then simulated, analysing changes in the distribution of stresses in the three layers when neglecting residual stresses. In the tri-layered model with residual stresses, layers exhibited comparable stresses throughout the physiological range of pressure. At 100 mmHg, intimal, medial, and adventitial circumferential load bearings were 16 ± 3%, 59 ± 4%, and 25 ± 2%, respectively. Adventitial stiffening at high pressures produced a shift in load bearing from the media to the adventitia. When neglecting residual stresses, in vivo stresses were highest at the intima and lowest at the adventitia. Consequently, the intimal and adventitial load bearings, 23 ± 2% and 18 ± 3% at 100 mmHg, were comparable at all pressures. Residual stresses play a crucial role in arterial mechanics guaranteeing a uniform distribution of stresses through the wall thickness. Neglecting these leads to incorrect interpretation of the layers’ role in arterial mechanics.
Giudici et al. (Mon,) conducted a other in Arterial mechanics (n=3). Tri-layered arterial wall modeling including residual stresses vs. Modeling neglecting residual stresses was evaluated on Distribution of circumferential load bearing among arterial layers at 100 mmHg. Including layer-specific residual stresses in a tri-layered arterial model demonstrated a uniform distribution of stresses through the wall thickness, whereas neglecting them incorrectly concentrated stresses at the intima.