Predicting Human Carotid Plaque Site of Rupture Using 3D Critical Plaque Wall Stress and Flow Shear Stress: A 3D Multi-Patient FSI Study Based on In Vivo MRI of Plaques With and Without Prior Rupture

Abstract

Atherosclerotic plaque rupture is the primary cause of cardiovascular clinical events such as heart attack and stroke. Image-based computational models of vulnerable plaques have been introduced seeking critical mechanical indicators which may be used to identify potential sites of rupture [1–5]. Models derived from 2D ex vivo and in vivo magnetic resonance images (MRI) have shown that 2D local critical stress values rather than global maximum stress values correlated better with plaque vulnerability, as defined by histopathological and morphological analyses [5]. A recent study by Tang et al. [4] using in vivo MRI-based 3D fluid-structure interaction (FSI) models for ruptured human carotid plaques, reported that mean plaque wall stress (PWS) values from ulcer nodes were 86% higher than mean PWS values from all non-ulcer nodes (p<0.0001). This study extends the “critical stress” concept to 3D and uses 3D FSI models based on in vivo MRI data of human atherosclerotic carotid plaques with and without prior rupture to identify 3D critical plaque wall stress (CPWS), critical flow shear stress (CFSS), and to investigate their associations with plaque rupture.