Cyclic Bending of Coronary Plaques Leads to Much Higher Stress Variations: A Major Factor Contributing to Plaque Rupture Risk

Mechanical forces play an important role in the complicated process of atherosclerotic plaque rupture which often leads to serious clinical events such as stroke and heart attack [4]. Factors causing the vulnerable plaque cap to fracture are important clinically [2–7]. It is known that coronary plaques are more likely to rupture compared to carotid plaques under comparable conditions (such as stenosis severity at about 50% by diameter). One possible reason is that coronary arteries are under cyclic bending caused by heart motions and compressions. We hypothesize that cyclic bending of coronary atherosclerotic plaques may be a major contributor to critical stress variations in the plaque leading to increased plaque rupture risk. We have developed MRI-based 3D multi-component models with fluid-structure interactions (FSI) in order to perform flow and stress/strain analysis for atherosclerotic plaques and identify possible mechanical and morphological indices for accurate plaque vulnerability assessment [6–7].