Past Event: PhD Dissertation Defense

Noninvasive Assessment of Coronary Artery Plaque Vulnerability

Michael Johnson, PhD Candidate

Abstract

Coronary artery disease (CAD) is a leading cause of death worldwide. It is caused by the buildup of atherosclerotic plaque in the coronary arteries. Over time these plaques may rupture, leading to acute coronary syndrome (ACS) such as heart attack and sudden cardiac death. Plaques that are associated with a high risk of rupture are often referred to as “vulnerable plaques.” The early identification of vulnerable plaques is essential in developing effective strategies for the diagnosis, prevention, and treatment of CAD.

   

Vulnerable plaques typically have large lipid-rich necrotic cores surrounded by a thin inflamed fibrous cap. Previous studies have suggested that high stresses in the fibrous cap are associated with increased risk of rupture and adverse clinical outcomes. Accordingly, I will focus on the development and application of a patient-specific biomechanical modeling framework for noninvasive estimation of cap stress using Coronary Computed Tomography Angiography (CCTA) and computational solid mechanics. First, I will analyze simplified lesion models using the theory of linear elasticity in order to derive a biomechanical characterization of  the morphology associated with vulnerable plaque. These results are then used to inform the key modeling considerations in the patient-specific setting. Next, I will present an overview of a numerical framework for automatic construction of patient-specific coronary lesion models, and accurate and efficient stress analysis of the fibrous cap. Finally, I will present results from a retrospective study of 209 coronary lesions that demonstrate the potential clinical utility of noninvasive estimates of cap stress.

Biography

Advisor: Tom Hughes