Background: Although several clinical and numerical studies have been conducted on plaque vulnerability
assessment, it still remains a critical target for investigation. The stresses whether because of the blood
pressure or stenting induce within plaque and arterial layers inside an atherosclerotic artery might exceed from
their yield stresses and trigger plaque rupture or arterial layer injury. This study is aimed at conducting a comparative
study to understand the vulnerability of the plaques, i.e., calcified, cellular, and hypocellular, as well as the
coronary arterial layers, i.e., intima, media, and adventitia, during the stent expansion inside a patient-specific
atherosclerotic coronary-artery model.
Methods: To do that, a three-dimensional (3D) finite element (FE) model of the atherosclerotic coronary artery is
established on a basis of CT/MRI data of a patient. The stent is then expanded inside the atherosclerotic artery
and the resulted stresses and strains in the plaque components, i.e., the fibrotic capsule (FC) and necrotic core
(NC), and arterial layers are computed.
Results: The results revealed that the distribution and magnitude of the von Mises stresses in each component
involved in stenting are different according to the plaque types and arterial layers. The stress in the calcified
plaque is the highest as compared to the cellular and hypocellular. Lower stresses are observed in the adjacent
medial and adventitial layers while the stress in the intima is high enough to invoke injury. The results suggest FC
and plaque rupture may occur at localized regions as well as plaque shoulders. Eventually, the dogboning and
foreshortening parameters found to be independent on that of the plaque types.
Conclusions: The results may have implications not only for understanding the vulnerable plaques and arterial
layers to rupture during the stenting, but also for providing a comprehensive information for the medical and
biomechanical experts in interventions and surgeries, including balloon-angioplasty, bypass, and stenting.