The atherosclerotic process starts early in life
and advances throughout adulthood when atherosclerotic disease
causes chronic angina, acute coronary and peripheral vascular
syndromes, stroke, and sudden death. Until recently, the occlusive
character of plaque was considered paramount. However, growing
evidence suggests that cardiovascular events are triggered by
plaque rupture and that the decisive risk factor is plaque composition
rather than morphology.
This multidisciplinary proposal develops a non-invasive
strategy for quantitative assessment of plaque vulnerability based
on multi-contrast three-dimensional MR imaging, automated segmentation
and plaque type characterization of volumetric data, and finite
element biomechanical modeling.
Hypotheses and Aims:
Overall Hypotheis: Mechanical behavior
of atherosclerotic lesions that is directly related to plaque
vulnerability can be determined non-invasively from three-dimensional
morphology and composition of plaque as depicted by MR imaging.
Aim 1: Develop three-dimensional MR imaging
strategies and protocols to non-invasively identify plaque morphology
and composition.
Aim2: Develop and validate a highly automated
method for plaque segmentation and characterization from three-dimensional
MR image data.
Aim 3: Develop a method for assessment
of plaque vulnerability by determination of mechanical properties
and behavior of plaque.
To maximize the relevance of our research and development, 40
fresh animal and 30 fresh human arteries with known atherosclerotic
lesions will be studied. The relationship between the plaque composition
of atherosclerotic lesions and the local biomechanical behavior
may further our understanding of the development of atherosclerosis
and the characteristics and mechanisms of vulnerable plaques that
lead to atherosclerosis disease progression and acute cardiovascular
events. For the first time, it will be possible to study the mechanics
and behavior of "real plaques" and their morphological and material
determinants on a quantitative basis.
