Strain imaging in echocardiography: methods and clinical applications

Echocardiography is the most common diagnostic method for assessing cardiac functions. However, echocardiographic measures are subjective, semi-quantitative, and relatively insensitive when detecting subtle perturbations in contractility. Furthermore, early detection of abnormalities is crucial and may often influence treatments and establish prognosis. Echocardiographic- and Doppler-derived strain and strain rate imaging are relatively newer and more comprehensive techniques. They characterize the mechanics of myocardial contraction and relaxation (deformation imaging) more precisely and find applications in many cardiac pathologies. They are especially useful for assessing longitudinal myocardial deformation, which is otherwise difficult to assess using standard echocardiographic visual inspection. This review describes the fundamental concepts of strain imaging derived from tissue Doppler and two-dimensional speckle tracking and investigates how these methods can be incorporated into echocardiographic examinations and highlights their clinical applications. The considerable potentiality of imaging modalities for numerous cardiac conditions is thereby shown.