Understanding of the structural-functional relationships of the heart, in both
normal and diseased states, is not complete without incorporating precise knowledge of
the underlying tissue microstructure, in terms of myocyte organization and orientation.
By probing the effects on the diffusion of water molecules exerted by their microscopic
environment, magnetic resonance diffusion tensor imaging (MR-DTI, or DTI for short)
has emerged as a promising alternative to conventional histology for mapping fiber
organization in ordered tissues such as the myocardium. In this chapter, the basic
principles and recent advances in mapping myocardial structure using DTI are
reviewed. Instances when DTI has advanced the understanding of the functionalstructural
relationship in the heart are also highlighted.
Diffusion-weighted MRI, diffusion tensor imaging (DTI), helix angle,
sheet angle, fractional anisotropy, mean diffusivity, tractography, myocardium,
left ventricle, right handed fibers, left handed fibers, circumferential fibers,
motion effects, ischemic disease, non-ischemic disease, hypertrophic
cardiomyopathy, dyssynchronous heart failure.
Department of Bioengineering, University of Utah, Utah, USA.