Tissue Doppler echocardiography

Tissue Doppler echocardiography, since its introduction more than 2 decades ago, had revolutionized echocardiography. In the quest to directly quantify myocardial function, increase sensitivity to detect early subtle myocardial dysfunction and improve ease of use, tissue Doppler echocardiography has evolved from pulsed wave tissue Doppler, to color-coded tissue Doppler and to 2-dimensional (2D) speckle tracking, and from myocardial velocity to strain/strain rate imaging. Over the years, numerous studies have demonstrated the value of tissue Doppler echocardiography in the diagnosis and risk stratification of a wide range of cardiac diseases. However, each generational change in tissue Doppler echocardiography involves technological software advancements that are not directly comparable to previous generations. To extensively present the technical differences between tissue Doppler imaging and speckle tracking analyses, and to review the clinical implications of myocardial velocity, strain and strain rate imaging by tissue Doppler versus speckle tracking, is well beyond the scope of the present article. Thus, the aim of the present review is to focus on tissue Doppler imaging, from basic physical principles and technical limitations, to differences in myocardial velocity, strain and strain rate imaging in healthy and diseased states, and finally the prognostic value of tissue Doppler deformation imaging in predicting adverse cardiac outcomes.