A comparison between the principal stress direction and collagen fiber orientation in coronary atherosclerotic plaque fibrous caps

The rupture of coronary atherosclerotic plaque fibrous caps has been associated with acute myocardial infarctions. Collagen fibers, the main structural component of vascular tissue, have been observed to change orientation and align themselves with the principal stress direction. This study compared the principal stress direction in stenosed coronary arteries obtained from 3D fluid–structure interaction simulations to the orientation of collagen fibers in the fibrous cap of human specimens. The principal stress direction at the peak of the stenosis was found to be axially oriented and correlated well with the determined orientation of the collagen fibers in the fibrous cap specimens.