Imaging cardiac mechanics: what information do we need to extract from cardiac images?

Cardiac mechanics attempts to relate loading (stress), deformation (strain), and material properties (stress-strain relationships) in the normal and diseased heart. Currently, imaging is employed in cardiac mechanics almost exclusively to track myocardial strains; a number of available methods and their relative strengths and weaknesses are discussed. Looking forward, reliable techniques to image stress or material properties (stiffness) would be immensely valuable contributions to cardiac mechanics, and better noninvasive techniques for imaging electrical activation patterns and ventricular synchrony could make important clinical contributions.