Cardiac pathologies are often characterized by important changes of myocardial properties such as the myocardial stiffness, re-organization of muscle fiber structure, modification of the microcirculation flow, all of which remain challenging to assess quantitatively and non-invasively in vivo. Over the last decade, the advent of software-based systems has enabled the implementation of ultrafast ultrasound imaging of the heart at 5000 images/s. Such a high frame rate has offered new possibilities for imaging quantitatively the myocardial function in 2D and 3D.