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Echocardiographic strain and strain-rate imaging (deformation imaging) is a new non-invasive method for assessment of myocardial function. While velocity and displacement characterize wall motion, strain and strain-rate describe wall deformation. Moving object will change its position (displacement) but does not undergo deformation if all its parts move with the same velocity. If, however, different parts of the object move with different velocities, the object will undergo deformation and will change its shape. The term “strain”, which in everyday language can mean “stretching”, is used in echocardiography to describe “deformation” and strain-rate is the velocity in this deformation.

The amount of deformation (positive or negative strain) is usually expressed in %. Positive strain values describe thickening, negative values describe shortening. Strain and strain rate measurements appeared to be sensitive indicators for sub-clinical diseases.